1
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Borkowski AK, Senanayake HS, Thompson WH. A generalized van't Hoff relation for the temperature dependence of complex-valued nonlinear spectra. J Chem Phys 2024; 161:064114. [PMID: 39140445 DOI: 10.1063/5.0220236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2024] [Accepted: 07/23/2024] [Indexed: 08/15/2024] Open
Abstract
The temperature dependence of spectra can reveal important insights into the structural and dynamical behavior of the system being probed. In the case of linear spectra, this has been exploited to investigate the thermodynamic driving forces governing the spectral response. Indeed, the temperature derivative of a spectrum can be used to obtain effective energetic and entropic profiles as a function of the measured frequency. The former can further be used to predict the temperature-dependent spectrum via a van't Hoff relation. However, these approaches are not directly applicable to nonlinear, complex-valued spectra, such as vibrational sum-frequency generation (SFG) or two-dimensional infrared (2D-IR) photon echo spectra. Here, we show how the energetic and entropic driving forces governing such nonlinear spectra can be determined and used within a generalized van't Hoff relation to predict their temperature dependence. The central idea is to allow the underlying energetic profiles to themselves be complex-valued. We illustrate this approach for 2D-IR spectra of water and SFG spectra of the air-water interface and demonstrate the accuracy of the generalized van't Hoff relationship and its implications for the origin of temperature-dependent spectral changes.
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Affiliation(s)
- Ashley K Borkowski
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
| | | | - Ward H Thompson
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
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2
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Huang C, Bai S, Shi Q. Simulation of the Pump-Probe Spectra and Excitation Energy Relaxation of the B850 Band of the LH2 Complex in Purple Bacteria. J Phys Chem B 2024; 128:7467-7475. [PMID: 39059418 DOI: 10.1021/acs.jpcb.4c02059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2024]
Abstract
Ultrafast spectroscopic techniques have been vital in studying excitation energy transfer (EET) in photosynthetic light harvesting complexes. In this paper, we simulate the pump-probe spectra of the B850 band of the light harvesting complex 2 (LH2) of purple bacteria, by using the hierarchical equation of motion method and the optical response function approach. The ground state bleach, stimulated emission, and excited state absorption components of the pump-probe spectra are analyzed in detail. The laser pulse-induced population dynamics are also simulated to help understand the main features of the pump-probe spectra and the EET process. It is shown that the excitation energy relaxation is an ultrafast process with multiple time scales. The first 40 fs of the pump-probe spectra is dominated by the relaxation of the k = ±1 states to both the k = 0 and higher energy states. Dynamics on a longer time scale around 200 fs reflects the relaxation of higher energy states to the k = 0 state.
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Affiliation(s)
- Chenghong Huang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun,Beijing 100190, China
- China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shuming Bai
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun,Beijing 100190, China
- China University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qiang Shi
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun,Beijing 100190, China
- China University of Chinese Academy of Sciences, Beijing 100049, China
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3
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de la Puente M, Laage D. Impact of interfacial curvature on molecular properties of aqueous interfaces. J Chem Phys 2024; 160:234504. [PMID: 38888129 DOI: 10.1063/5.0210884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 05/28/2024] [Indexed: 06/20/2024] Open
Abstract
The curvature of soft interfaces plays a crucial role in determining their mechanical and thermodynamic properties, both at macroscopic and microscopic scales. In the case of air/water interfaces, particular attention has recently focused on water microdroplets, due to their distinctive chemical reactivity. However, the specific impact of curvature on the molecular properties of interfacial water and interfacial reactivity has so far remained elusive. Here, we use molecular dynamics simulations to determine the effect of curvature on a broad range of structural, dynamical, and thermodynamical properties of the interface. For a droplet, a flat interface, and a cavity, we successively examine the structure of the hydrogen-bond network and its relation to vibrational spectroscopy, the dynamics of water translation, rotation, and hydrogen-bond exchanges, and the thermodynamics of ion solvation and ion-pair dissociation. Our simulations show that curvature predominantly impacts the hydrogen-bond structure through the fraction of dangling OH groups and the dynamics of interfacial water molecules. In contrast, curvature has a limited effect on solvation and ion-pair dissociation thermodynamics. For water microdroplets, this suggests that the curvature alone cannot fully account for the distinctive reactivity measured in these systems, which are of great importance for catalysis and atmospheric chemistry.
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Affiliation(s)
- M de la Puente
- PASTEUR, Department of Chemistry, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - D Laage
- PASTEUR, Department of Chemistry, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
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4
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Pei R, Zhang J, Tan J, Luo Y, Ye S. Fermi Resonance of the N-D Stretching Mode Probing the Local Hydrogen-Bonding Environment in Proteins. J Phys Chem B 2024; 128:5658-5666. [PMID: 38836292 DOI: 10.1021/acs.jpcb.4c00390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
Local H-bonding interactions are crucial for proteins to undergo various structural transitions and form different secondary structures. However, identifying slight distinctions in the local H-bonding of proteins is rather challenging. Here, we demonstrate that the Fermi resonance of the N-D stretching mode can provide an effective probe for the localized H-bonding environment of proteins both at the surface/interface and in the bulk. Using sum frequency generation vibrational spectroscopy and infrared spectroscopy, we established a correlation between the Fermi resonance of the N-D mode and protein secondary structures. The H-bond of N-D···C═O splits the N-D modes into two peaks (∼2410 and ∼2470 cm-1). The relative strength ratio (R) between the ∼2410 cm-1 peak and the ∼2470 cm-1 peak is very sensitive to H-bond strength and protein secondary structure. R is less than 1 for α-helical peptides, while R is greater than 1 for β-sheet peptides. For R < 2.5, both α-helical/loop structures and β-sheet structures exhibit almost identical Fermi coupling strengths (W = 28 cm-1). For R > 2.5, W decreases from 28 to 14 cm-1 and depends on the aggregation degree of the β-sheet oligomers or fibrils. The initial local H-bonding status impacts the misfolding dynamics of proteins at the lipid bilayer interface.
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Affiliation(s)
- Ruoqi Pei
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Jiahui Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Junjun Tan
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Yi Luo
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Shuji Ye
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
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5
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Takayama T, Otosu T, Yamaguchi S. Theoretical and experimental OD-stretch vibrational spectroscopy of heavy water. J Chem Phys 2024; 160:104504. [PMID: 38465684 DOI: 10.1063/5.0200623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Accepted: 02/22/2024] [Indexed: 03/12/2024] Open
Abstract
In view of the current situation in which the OD-stretch vibrational spectra have been scarcely computed with non-polarizable rigid D2O models, we investigate the IR and Raman spectra of D2O by using a newly-reported model TIP4P/2005-HW. From the comparison between the calculations and experimental data, we find the excellent performance of TIP4P/2005-HW for vibrational spectroscopy of D2O in the same manner as TIP4P/2005 for H2O, although one may still conveniently employ an alternative method that regards OH as putative OD to calculate the OD-stretch spectra with similar quality from TIP4P/2005 trajectories. We also demonstrate that the appropriate setting for the spectral simulation of D2O under the time-averaging approximation reflects the slower dynamics (i.e., slower motion of translation and rotation due to the heavier mass and stronger hydrogen bond) of D2O than H2O. Moreover, we show from the theoretical calculations that the established interpretation of the OH-stretch spectra of H2O is finely applicable to the OD-stretch of D2O.
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Affiliation(s)
- Tetsuyuki Takayama
- Department of Applied Chemistry, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura, Saitama 338-8570, Japan
| | - Takuhiro Otosu
- Department of Applied Chemistry, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura, Saitama 338-8570, Japan
| | - Shoichi Yamaguchi
- Department of Applied Chemistry, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura, Saitama 338-8570, Japan
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6
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Sayer T, Montoya-Castillo A. Efficient formulation of multitime generalized quantum master equations: Taming the cost of simulating 2D spectra. J Chem Phys 2024; 160:044108. [PMID: 38270238 DOI: 10.1063/5.0185578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 12/26/2023] [Indexed: 01/26/2024] Open
Abstract
Modern 4-wave mixing spectroscopies are expensive to obtain experimentally and computationally. In certain cases, the unfavorable scaling of quantum dynamics problems can be improved using a generalized quantum master equation (GQME) approach. However, the inclusion of multiple (light-matter) interactions complicates the equation of motion and leads to seemingly unavoidable cubic scaling in time. In this paper, we present a formulation that greatly simplifies and reduces the computational cost of previous work that extended the GQME framework to treat arbitrary numbers of quantum measurements. Specifically, we remove the time derivatives of quantum correlation functions from the modified Mori-Nakajima-Zwanzig framework by switching to a discrete-convolution implementation inspired by the transfer tensor approach. We then demonstrate the method's capabilities by simulating 2D electronic spectra for the excitation-energy-transfer dimer model. In our method, the resolution of data can be arbitrarily coarsened, especially along the t2 axis, which mirrors how the data are obtained experimentally. Even in a modest case, this demands O(103) fewer data points. We are further able to decompose the spectra into one-, two-, and three-time correlations, showing how and when the system enters a Markovian regime where further measurements are unnecessary to predict future spectra and the scaling becomes quadratic. This offers the ability to generate long-time spectra using only short-time data, enabling access to timescales previously beyond the reach of standard methodologies.
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Affiliation(s)
- Thomas Sayer
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, USA
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7
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Zhu H, Chen B, Yakovlev VV, Zhang D. Time-resolved vibrational dynamics: Novel opportunities for sensing and imaging. Talanta 2024; 266:125046. [PMID: 37595525 DOI: 10.1016/j.talanta.2023.125046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/19/2023] [Accepted: 08/05/2023] [Indexed: 08/20/2023]
Abstract
The evolution of time-resolved spectroscopies has resulted in significant advancements across numerous scientific disciplines, particularly those concerned with molecular electronic states. However, the intricacy of molecular vibrational spectroscopies, which provide comprehensive molecular-level information within complex structures, has presented considerable challenges due to the ultrashort dephasing time. Over recent decades, an increasing focus has been placed on exploring the temporal progression of bond vibrations, thereby facilitating an improved understanding of energy redistribution within and between molecules. This review article focuses on an array of time-resolved detection methodologies, each distinguished by unique technological attributes that offer exclusive capabilities for investigating the physical phenomena propelled by molecular vibrational dynamics. In summary, time-resolved vibrational spectroscopy emerges as a potent instrument for deciphering the dynamic behavior of molecules. Its potential for driving future progress across fields as diverse as biology and materials science is substantial, marking a promising future for this innovative tool.
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Affiliation(s)
- Hanlin Zhu
- Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, and Department of Physics, Zhejiang University, Hangzhou, Zhejiang, 310028, China.
| | - Bo Chen
- Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, and Department of Physics, Zhejiang University, Hangzhou, Zhejiang, 310028, China.
| | - Vladislav V Yakovlev
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA; Department of Physics and Astronomy, Texas A&M University, College Station, TX, 77843, USA; Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX, 77843, USA.
| | - Delong Zhang
- Interdisciplinary Center for Quantum Information, Zhejiang Province Key Laboratory of Quantum Technology and Device, and Department of Physics, Zhejiang University, Hangzhou, Zhejiang, 310028, China.
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8
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Wiethorn ZR, Hunter KE, Zuehlsdorff TJ, Montoya-Castillo A. Beyond the Condon limit: Condensed phase optical spectra from atomistic simulations. J Chem Phys 2023; 159:244114. [PMID: 38153146 DOI: 10.1063/5.0180405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 12/06/2023] [Indexed: 12/29/2023] Open
Abstract
While dark transitions made bright by molecular motions determine the optoelectronic properties of many materials, simulating such non-Condon effects in condensed phase spectroscopy remains a fundamental challenge. We derive a Gaussian theory to predict and analyze condensed phase optical spectra beyond the Condon limit. Our theory introduces novel quantities that encode how nuclear motions modulate the energy gap and transition dipole of electronic transitions in the form of spectral densities. By formulating the theory through a statistical framework of thermal averages and fluctuations, we circumvent the limitations of widely used microscopically harmonic theories, allowing us to tackle systems with generally anharmonic atomistic interactions and non-Condon fluctuations of arbitrary strength. We show how to calculate these spectral densities using first-principles simulations, capturing realistic molecular interactions and incorporating finite-temperature, disorder, and dynamical effects. Our theory accurately predicts the spectra of systems known to exhibit strong non-Condon effects (phenolate in various solvents) and reveals distinct mechanisms for electronic peak splitting: timescale separation of modes that tune non-Condon effects and spectral interference from correlated energy gap and transition dipole fluctuations. We further introduce analysis tools to identify how intramolecular vibrations, solute-solvent interactions, and environmental polarization effects impact dark transitions. Moreover, we prove an upper bound on the strength of cross correlated energy gap and transition dipole fluctuations, thereby elucidating a simple condition that a system must follow for our theory to accurately predict its spectrum.
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Affiliation(s)
- Zachary R Wiethorn
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, USA
| | - Kye E Hunter
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, USA
| | - Tim J Zuehlsdorff
- Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, USA
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9
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LaCour RA, Heindel JP, Head-Gordon T. Predicting the Raman Spectra of Liquid Water with a Monomer-Field Model. J Phys Chem Lett 2023; 14:11742-11749. [PMID: 38116782 DOI: 10.1021/acs.jpclett.3c02873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
The Raman spectrum of liquid water is quite complex, reflecting its strong sensitivity to the local environment of the individual waters. The OH-stretch region of the spectrum, which captures the influence of hydrogen bonding, has only just begun to be unraveled. Here we develop a model for predicting the Raman spectra of the OH-stretch region by considering how local electric fields distort the energy surface of each water monomer. We find that our model is capable of reproducing the bimodal nature of the main peak, with the shoulder at 3250 cm-1 resulting almost entirely from Fermi resonance. Furthermore, we capture the temperature and polarization dependence of the shoulder, which has proven to be difficult to obtain with previous methods, and analyze the origin of this dependence. We expect our model to be generally useful for understanding and predicting how Raman spectra change under different conditions and with different probe reporters beyond water.
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Affiliation(s)
- R Allen LaCour
- Kenneth S. Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Joseph P Heindel
- Kenneth S. Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Teresa Head-Gordon
- Kenneth S. Pitzer Theory Center and Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Departments of Bioengineering and Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
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10
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Bodine M, Rozyyev V, Elam JW, Tokmakoff A, Lewis NHC. Vibrational Probe at the Electrochemical Interface: Dependence on Plasmon Coupling and Potential of the Lineshape in Two-Dimensional Infrared Spectroscopy. J Phys Chem Lett 2023:11092-11099. [PMID: 38051916 DOI: 10.1021/acs.jpclett.3c02987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
Two-dimensional infrared spectroscopy of vibrational probes at an electrode surface shows promise for studying the structural dynamics at an active electrochemical interface. This interface is a complex environment where the solution structures in response to the applied potential. A strategy for achieving the necessary monolayer sensitivity is to use a plasmonically active electrode, which enhances the electromagnetic fields that produce the spectroscopic response. Here, we show how the coupling between the plasmon and the vibrations of the molecular monolayer impacts the FTIR and 2D IR spectroscopy, with an emphasis on the electrochemical potential difference spectra. We show how mixing between the vibrational and plasmonic states gives rise to the distortions that are observed in these measurements. This provides an important step toward 2D IR measurements of vibrational probes at the electrochemical interface as a tool for probing the structural dynamics in the double layer.
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Affiliation(s)
- Melissa Bodine
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, United States
| | - Vepa Rozyyev
- Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States
- Applied Materials Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Jeffrey W Elam
- Applied Materials Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Andrei Tokmakoff
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, United States
| | - Nicholas H C Lewis
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, United States
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11
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Malik R, Chandra A. Counteracting Effects of Trimethylamine N-Oxide against Urea in Aqueous Solutions: Insights from Theoretical Two-Dimensional Infrared Spectroscopy. J Phys Chem B 2023; 127:7372-7383. [PMID: 37566900 DOI: 10.1021/acs.jpcb.3c03864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/13/2023]
Abstract
The study of small osmolytes in their aqueous solutions has gained significant attention because of their relevance to structure and thermodynamics of proteins in aqueous media. Special attention has been given to the binary and ternary aqueous solutions of urea and trimethylamine N-oxide (TMAO). Urea is a well-known protein denaturant, while TMAO protects proteins in their native states. Interestingly, TMAO counteracts urea's ability to denature proteins when present in solutions with approximately half of the concentration of urea. Vibrational spectroscopy can improve our understanding of the molecular origin of this counteracting effect because of its sensitivity to local structure and dynamics. We present results of theoretical linear vibrational and two-dimensional infrared (2DIR) spectroscopy of water in the binary and ternary aqueous solutions of TMAO and urea. The 2DIR spectra are calculated using the electronic structure/molecular dynamics approach. The non-Condon effects in spectral transitions are incorporated in the theoretical calculations of 2DIR spectra. It is found that TMAO disrupts the local structure of water, while urea leaves it essentially unaffected. The 2DIR results show that both TMAO and urea slow down the dynamics of spectral diffusion of water. The extent of slowing down is found to be particularly significant for both hydration and bulk water in the presence of TMAO which can be attributed to strong hydrogen bonds between the water and TMAO molecules. The water molecules present in the hydration layer of the solutes in the ternary solutions are found to relax at even slower rates compared to that in their binary solutions in water. The hydrogen bonds between TMAO and urea are found to be not stable. Thus, the counteracting effect of TMAO against urea is seen to take place mainly through water-mediated interactions. Such TMAO-induced effects giving rise to more structured and slower hydrogen-bonded network are successfully captured through 2DIR spectroscopic calculations.
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Affiliation(s)
- Ravi Malik
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India
| | - Amalendu Chandra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India
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12
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Torii H, Watanabe K. Asymmetry of the Electrostatic Environment as the Origin of the Symmetry Breaking Effect of the Nitrate Ion in Aqueous Solution. J Phys Chem B 2023; 127:6507-6515. [PMID: 37462156 DOI: 10.1021/acs.jpcb.3c01977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2023]
Abstract
Elucidating the mechanism of how vibrational modes are affected by intermolecular interactions is important for a better understanding of the nature of the former as probes of the latter. Here, such an analysis is carried out for the N-O stretching modes of the nitrate ion interacting with water, with an emphasis on the symmetry breaking effect. On the basis of theoretical calculations on the structural, vibrational, and electrostatic properties of molecular clusters and spectral simulations for an aqueous solution, a transparent view is demonstrated on the mechanism that modulations of spatially local electrostatic environment give rise to structural and spectroscopic symmetry breaking effect. The electrostatic interaction model constructed here is a seven-parameter model; the use of a single electrostatic parameter, such as the electric field on a single atomic site, is found to be insufficient for quantitative evaluation. It is also shown that the frequency modulations of the N-O stretching modes in aqueous solution occur on a time scale much shorter than 0.1 ps.
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Affiliation(s)
- Hajime Torii
- Department of Applied Chemistry and Biochemical Engineering, Faculty of Engineering, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561, Japan
- Department of Optoelectronics and Nanostructure Science, Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561, Japan
| | - Kao Watanabe
- Department of Applied Chemistry and Biochemical Engineering, Faculty of Engineering, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561, Japan
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13
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Wang Y, Chen Z, Yang Y. Calculating Vibrational Excited State Absorptions with Excited State Constrained Minimized Energy Surfaces. J Phys Chem A 2023. [PMID: 37335973 DOI: 10.1021/acs.jpca.3c01420] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2023]
Abstract
The modeling and interpretation of vibrational spectra are crucial for studying reaction dynamics using vibrational spectroscopy. Most prior theoretical developments focused on describing fundamental vibrational transitions while fewer developments focused on vibrational excited state absorptions. In this study, we present a new method that uses excited state constrained minimized energy surfaces (CMESs) to describe vibrational excited state absorptions. The excited state CMESs are obtained similarly to the previous ground state CMES development in our group but with additional wave function orthogonality constraints. Using a series of model systems, including the harmonic oscillator, Morse potential, double-well potential, quartic potential, and two-dimensional anharmonic potential, we demonstrate that this new procedure provides good estimations of the transition frequencies for vibrational excited state absorptions. These results are significantly better than those obtained from harmonic approximations using conventional potential energy surfaces, demonstrating the promise of excited state CMES-based methods for calculating vibrational excited state absorptions in real systems.
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Affiliation(s)
- Yiwen Wang
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Zehua Chen
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Yang Yang
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin─Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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14
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Roget SA, Heck TR, Carter-Fenk KA, Fayer MD. Ion/Water Network Structural Dynamics in Highly Concentrated Lithium Chloride and Lithium Bromide Solutions Probed with Ultrafast Infrared Spectroscopy. J Phys Chem B 2023; 127:4532-4543. [PMID: 37172191 DOI: 10.1021/acs.jpcb.2c08792] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The structural dynamics of highly concentrated LiCl and LiBr aqueous solutions were observed from 1-4 to 1-16 water molecules per ion pair using ultrafast polarization-selective pump-probe (PSPP) experiments on the OD stretch of dilute HOD. At these high salt concentrations, an extended ion/water network exists with complex structural dynamics. Population decays from PSPP experiments highlight two distinct water components. From the frequency-dependent amplitudes of the decays, the spectra of hydroxyls bound to halides and to water oxygens are obtained, which are not observable in the FT-IR spectra. PSPP experiments also measure frequency-dependent water orientational relaxation. At short times, wobbling dynamics within a restricted angular cone occurs. At high concentrations, the cone angles are dependent on frequency (hydrogen bond strength), but at higher water concentrations (>10 waters per ion pair), there is no frequency dependence. The average cone angle increases as the ion concentration decreases. The slow time constant for complete HOD orientational relaxation is independent of concentration but slower in LiCl than in LiBr. Comparison to structural MD simulations of LiCl from the literature indicates that the loss of the cone angle wavelength dependence and the increase in the cone angles as the concentration decreases occur as the prevalence of large ion/water clusters gives way to contact ion pairs.
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Affiliation(s)
- Sean A Roget
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Tristan R Heck
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | | | - Michael D Fayer
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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15
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Malik R, Das B, Chandra A. Theoretical Two Dimensional Infrared Spectroscopy of Aqueous Solutions of tert-Butyl Alcohol: Variation of the Dynamics of Spectral Diffusion along the Percolation Transition. J Phys Chem B 2023; 127:4099-4111. [PMID: 37126459 DOI: 10.1021/acs.jpcb.2c08916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Binary mixtures of water and tert-butyl alcohol (TBA) are known to exhibit the so-called percolation transition where small clusters of TBA molecules span into large aggregates beyond a threshold concentration of the alcohol. In the present study, we have investigated the linear and two-dimensional infrared spectral features of aqueous solutions of TBA for varying concentration of the alcohol along the percolation transition. The percolation transition is characterized through calculations of intermolecular radial distribution functions and average size of the largest cluster of TBA molecules. It is found that, with variation of alcohol concentration, the radial distribution functions of the central carbon atoms of TBA molecules show a nonmonotonic change in the height of the first peak and also the size of the largest cluster of TBA molecules show a jump in the increase of its size for TBA mole fraction between 0.04 and 0.06 corresponding to a transition from smaller clusters to larger spanning aggregates. However, it is found that the linear infrared spectrum of water does not exhibit any noticeable changes on variation of TBA concentration along the percolation transition. Subsequently, two-dimensional infrared (2DIR) spectra and vibrational frequency time correlation function of water are calculated for all the TBA-water solutions considered in this study. The spectral diffusion of water calculated from 2DIR is found to slow down with increase of the TBA concentration. The time scales of spectral diffusion of water, as characterized by the relaxation of frequency time correlation function, 2DIR metric of central line slope, and also the hydrogen bond time correlation functions, are found to exhibit a noticeable jump along the percolation transition. The hydrophilic group of TBA is found to retard the water dynamics more effectively than the hydrophobic groups. Also, the jump in the dynamical slowdown along the percolation transition is found to be more significant for water molecules at the hydrophilic sites.
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Affiliation(s)
- Ravi Malik
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Banshi Das
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Amalendu Chandra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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Begušić T, Blake GA. Two-dimensional infrared-Raman spectroscopy as a probe of water's tetrahedrality. Nat Commun 2023; 14:1950. [PMID: 37029146 PMCID: PMC10082090 DOI: 10.1038/s41467-023-37667-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 03/22/2023] [Indexed: 04/09/2023] Open
Abstract
Two-dimensional spectroscopic techniques combining terahertz (THz), infrared (IR), and visible pulses offer a wealth of information about coupling among vibrational modes in molecular liquids, thus providing a promising probe of their local structure. However, the capabilities of these spectroscopies are still largely unexplored due to experimental limitations and inherently weak nonlinear signals. Here, through a combination of equilibrium-nonequilibrium molecular dynamics (MD) and a tailored spectrum decomposition scheme, we identify a relationship between the tetrahedral order of liquid water and its two-dimensional IR-IR-Raman (IIR) spectrum. The structure-spectrum relationship can explain the temperature dependence of the spectral features corresponding to the anharmonic coupling between low-frequency intermolecular and high-frequency intramolecular vibrational modes of water. In light of these results, we propose new experiments and discuss the implications for the study of tetrahedrality of liquid water.
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Affiliation(s)
- Tomislav Begušić
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA.
| | - Geoffrey A Blake
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA.
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, 91125, USA.
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Malik R, Chandra A, Das B, Chandra A. Temperature Dependence of Non-Condon Effects in Two-Dimensional Vibrational Spectroscopy of Water. J Phys Chem B 2023; 127:2488-2498. [PMID: 36893383 DOI: 10.1021/acs.jpcb.2c06794] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
Non-Condon effects in vibrational spectroscopy refers to the dependence of a molecule's vibrational transition dipole and polarizability on the coordinates of the surrounding environment. Earlier studies have shown that such effects can be pronounced for hydrogen-bonded systems like liquid water. Here, we present a theoretical study of two-dimensional vibrational spectroscopy under the non-Condon and Condon approximations at varying temperatures. We have performed calculations of both two-dimensional infrared and two-dimensional vibrational Raman spectra to gain insights into the temperature dependence of non-Condon effects in nonlinear vibrational spectroscopy. The two-dimensional spectra are calculated for the OH vibration of interest in the isotopic dilution limit where the coupling between the oscillators is ignored. Generally, both the infrared and Raman line shapes undergo red shifts with decrease in temperature due to strengthening of hydrogen bonds and decrease in the fraction of OH modes with weaker or no hydrogen bonds. The infrared line shape is further red-shifted under the non-Condon effects at a given temperature, while the Raman line shape does not show any such red shift due to non-Condon effects. The spectral dynamics becomes slower on decrease of temperature due to slower hydrogen bond relaxation and, for a given temperature, the spectral diffusion occurs at a faster rate upon inclusion of non-Condon effects. The time scales of spectral diffusion extracted from different metrics agree well with each other and also with experiments. The changes in the spectrum due to non-Condon effects are found to be more significant at lower temperatures.
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Affiliation(s)
- Ravi Malik
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Abhilash Chandra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Banshi Das
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Amalendu Chandra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, India
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18
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Meng W, Peng HC, Liu Y, Stelling A, Wang L. Modeling the Infrared Spectroscopy of Oligonucleotides with 13C Isotope Labels. J Phys Chem B 2023; 127:2351-2361. [PMID: 36898003 DOI: 10.1021/acs.jpcb.2c08915] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
The carbonyl stretching modes have been widely used in linear and two-dimensional infrared (IR) spectroscopy to probe the conformation, interaction, and biological functions of nucleic acids. However, due to their universal appearance in nucleobases, the IR absorption bands of nucleic acids are often highly congested in the 1600-1800 cm-1 region. Following the fruitful applications in proteins, 13C isotope labels have been introduced to the IR measurements of oligonucleotides to reveal their site-specific structural fluctuations and hydrogen bonding conditions. In this work, we combine recently developed frequency and coupling maps to develop a theoretical strategy that models the IR spectra of oligonucleotides with 13C labels directly from molecular dynamics simulations. We apply the theoretical method to nucleoside 5'-monophosphates and DNA double helices and demonstrate how elements of the vibrational Hamiltonian determine the spectral features and their changes upon isotope labeling. Using the double helices as examples, we show that the calculated IR spectra are in good agreement with experiments and the 13C isotope labeling technique can potentially be applied to characterize the stacking configurations and secondary structures of nucleic acids.
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Affiliation(s)
- Wenting Meng
- Department of Chemistry and Chemical Biology, Institute for Quantitative Biomedicine, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Hao-Che Peng
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Yuanhao Liu
- Department of Statistics, Institute for Quantitative Biomedicine, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Allison Stelling
- Department of Chemistry and Biochemistry, The University of Texas at Dallas, Richardson, Texas 75080, United States
| | - Lu Wang
- Department of Chemistry and Chemical Biology, Institute for Quantitative Biomedicine, Rutgers University, Piscataway, New Jersey 08854, United States
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19
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Solvation structure and dynamics of a small ion in an organic electrolyte. J Photochem Photobiol A Chem 2023. [DOI: 10.1016/j.jphotochem.2023.114666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
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20
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Borkowski AK, Campbell NI, Thompson WH. Direct calculation of the temperature dependence of 2D-IR spectra: Urea in water. J Chem Phys 2023; 158:064507. [PMID: 36792517 DOI: 10.1063/5.0135627] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
A method for directly calculating the temperature derivative of two-dimensional infrared (2D-IR) spectra from simulations at a single temperature is presented. The approach is demonstrated by application to the OD stretching spectrum of isotopically dilute aqueous (HOD in H2O) solutions of urea as a function of concentration. Urea is an important osmolyte because of its ability to denature proteins, which has motivated significant interest in its effect on the structure and dynamics of water. The present results show that the temperature dependence of both the linear IR and 2D-IR spectra, which report on the underlying energetic driving forces, is more sensitive to urea concentration than the spectra themselves. Additional physical insight is provided by calculation of the contributions to the temperature derivative from different interactions, e.g., water-water, water-urea, and urea-urea, present in the system. Finally, it is demonstrated how 2D-IR spectra at other temperatures can be obtained from only room temperature simulations.
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Affiliation(s)
- Ashley K Borkowski
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
| | - N Ian Campbell
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
| | - Ward H Thompson
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
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21
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Unified master equation for molecules in phonon and radiation baths. Sci Rep 2022; 12:20015. [DOI: 10.1038/s41598-022-22732-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 10/19/2022] [Indexed: 11/23/2022] Open
Abstract
AbstractWe have developed a unified quantum optical master equation that includes the dissipative mechanisms of an impurity molecule in crystals. Our theory applies generally to polyatomic molecules where several vibrational modes give rise to intramolecular vibrational redistributions. The usual assumption on identical shapes of the nuclear potentials in ground and excited electronic states and the rotating wave approximation have been relaxed, i.e. the vibrational coordinates are different in the ground and excited states, with counter-rotating terms included for generality. Linear vibrational coupling to the lattice phonons accounts for dissipations via non-radiative transitions. The interaction of a molecule with photons includes Herzberg–Teller coupling as the first order non-Condon interaction where the transition dipole matrix elements depend linearly on vibrational coordinates. We obtain new cross terms as the result of mixing the terms from the zeroth-order (Condon) and first-order (non-Condon) approximations. The corresponding Lamb shifts for all Liouvilleans are derived explicitly including the contributions of counter-rotating terms. The computed absorption and emission spectra for carbon monoxide is in good agreement with experimental data. We use our unified model to obtain the spectra for nitrogen dioxide, demonstrating the capability of our theory to incorporate all typical dissipative relaxation and decoherence mechanisms for polyatomic molecules. The molecular quantum master equation is a promising theory for studying molecular quantum memory.
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Biswas A, Mallik BS. Molecular Simulation-Guided Spectroscopy of Imidazolium-Based Ionic Liquids and Effects of Methylation on Ion-Cage and -Pair Dynamics. J Phys Chem B 2022; 126:8838-8850. [PMID: 36264223 DOI: 10.1021/acs.jpcb.2c04901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Classical molecular dynamics simulations were performed to assess an atomistic interpretation of the ion-probe structural interactions in two typical ionic liquids (ILs), 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [BMIm][NTf2] and 1-butyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)imide [BDimIm][NTf2] through computational ultrafast spectroscopy. The nitrile stretching vibrations of the thiocyanate anion, [SCN]-, serve as the local mode of the ultrafast system dynamics within the imidazolium-based ionic liquid environment. The wavelet transform of classical trajectories determines the time-varying fluctuating frequencies and the stretch spectral signatures of SCN- in the normalized distribution. However, computational modeling of the two-dimensional (2D) spectra from the wavelet-derived vibrational frequencies yields time evolution of the local molecular structure along with the varied time-dependent dynamics of the spectral diffusion process. We calculated the frequency-frequency correlation functions (FFCFs), time correlations associated with the ion-pair and -cage dynamics, and mean square displacements as a function of time, depicting diffusive dynamics. The calculated results based on the pair correlation functions and the distribution of atomic density suggest that the hydrogen and methylated carbon at the two-position of the imidazolium ring of [BMIm] and [BDimIm] cations, respectively, strongly interact with the probe through the N of the thiocyanate anion rather than the S atom. The center-of-mass center-of-mass (COM-COM) cation-probe radial distribution functions (RDFs) in conjunction with the site-specific structural analysis further reveal well-structured interactions of the thiocyanate ion and [BMIm]+ cation rather than the [BDimIm] cation. In contrast, the anion-probe COM-COM RDFs depict weak interactive associations within the vibrational probe [SCN]- and [NTf2]- ions. Methylation at the two-position of the imidazolium ring predicts slower structural reorganization and breaking and reformation dynamics of the ion pairs and cages within the ionic liquid framework.
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Affiliation(s)
- Aritri Biswas
- Department of Chemistry, Indian Institute of Technology Hyderabad, Sangareddy502285, Telangana, India
| | - Bhabani S Mallik
- Department of Chemistry, Indian Institute of Technology Hyderabad, Sangareddy502285, Telangana, India
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Yamaguchi S, Takayama T, Goto Y, Otosu T, Yagasaki T. Experimental and Theoretical Heterodyne-Detected Sum Frequency Generation Spectroscopy of Isotopically Pure and Diluted Water Surfaces. J Phys Chem Lett 2022; 13:9649-9653. [PMID: 36214521 DOI: 10.1021/acs.jpclett.2c02533] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The χ(2) (second-order nonlinear optical susceptibility) spectrum of the water surface has been a matter of debate for a few decades. Here, we report that we experimentally measured the isotopic dilution dependence of the χ(2) spectrum and theoretically reproduced it by employing the quantum/classical mixed approach with a new idea to subtract an artifact. The present theoretical framework allows for clarifying the effects of the intramolecular, intermolecular, and Fermi resonance couplings on the OH-stretch vibrational spectra of water at the surface as well as in the bulk.
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Affiliation(s)
- Shoichi Yamaguchi
- Department of Applied Chemistry, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura, Saitama 338-8570, Japan
| | - Tetsuyuki Takayama
- Department of Applied Chemistry, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura, Saitama 338-8570, Japan
| | - Yuki Goto
- Department of Applied Chemistry, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura, Saitama 338-8570, Japan
| | - Takuhiro Otosu
- Department of Applied Chemistry, Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura, Saitama 338-8570, Japan
| | - Takuma Yagasaki
- Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, Toyonaka 560-8531, Japan
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24
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Borkowski AK, Thompson WH. Shining (Infrared) Light on the Hofmeister Series: Driving Forces for Changes in the Water Vibrational Spectra in Alkali-Halide Salt Solutions. J Phys Chem B 2022; 126:6700-6712. [PMID: 36004804 DOI: 10.1021/acs.jpcb.2c03957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Hofmeister series is frequently used to rank ions based on their behavior from chaotropes ("structure breakers"), which weaken the surrounding hydrogen-bond network, to kosmotropes ("structure makers"), which enhance it. Here, we use fluctuation theory to investigate the energetic and entropic driving forces underlying the Hofmeister series for aqueous alkali-halide solutions. Specifically, we exploit the OH stretch infrared (IR) spectrum in isotopically dilute HOD/D2O solutions as a probe of the effect of the salt on the water properties for different concentrations and choice of halide anion. Fluctuation theory is used to calculate the temperature derivative of these IR spectra, including decomposition of the derivative into different energetic contributions. These contributions are used to determine the thermodynamic driving forces in terms of effective internal energy and entropic contributions. This analysis implicates entropic contributions as the key factor in the Hofmeister series behavior of the OH stretch IR spectra, while the effective internal energy is nearly ion-independent.
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Affiliation(s)
- Ashley K Borkowski
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Ward H Thompson
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
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25
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Biswas A, Mallik BS. Multiple Ensembles of the Hydrogen-bonded Network in Ethylammonium Nitrate versus Water from Vibrational Spectral Dynamics of SCN- Probe. Chemphyschem 2022; 23:e202200497. [PMID: 35965410 DOI: 10.1002/cphc.202200497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/05/2022] [Indexed: 11/12/2022]
Abstract
We performed classical molecular dynamics simulations to monitor the structural interactions and ultrafast dynamical and spectral response in the protic ionic liquid, ethylammonium nitrate (EAN) and water using the nitrile stretching mode of thiocyanate ion (SCN-) as the vibrational probe. The normalized stretch frequency distribution of nitrile stretch of SCN- attains an asymmetric shape in EAN, indicating the existence of more than one hydrogen-bonding environment in EAN. We computed the 2D IR spectrum from classical trajectories, applying the response function formalism. Spectral diffusion dynamics in EAN undergo an initial rattling of the SCN - inside the local ion-cage occurring at a timescale of 0.10 ps, followed by the breakup of the ion-cage activating molecular diffusion at 7.86 ps timescale. In contrast, the dynamics of structural reorganization occur at a timescale of 0.58 ps in H 2 O. Hence, the time dependence of the frequency-frequency correlation function decay hints at the local molecular structure and ultrafast ion dynamics of the SCN - probe. The loss of frequency correlation read from the peak shape changes in the 2D correlation spectrum as a function of waiting time is faster in H 2 O than in EAN due to the enhanced structural ordering and higher viscosity of the latter. We provide an atomic-level interpretation of the solvation environment around SCN - in EAN and water, which indicates the multiple ensembles of the hydrogen bond network in EAN.
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Affiliation(s)
- Aritri Biswas
- IITH: Indian Institute of Technology Hyderabad, Chemistry, INDIA
| | - Bhabani S Mallik
- IITH: Indian Institute of Technology Hyderabad, Chemistry, Kandi, 502285, Sangareddy, INDIA
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26
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Biswas A, Mallik BS. Ionic Dynamics and Vibrational Spectral Diffusion of a Protic Alkylammonium Ionic Salt through Intrinsic Cationic N-H Vibrational Probe from FPMD Simulations. J Phys Chem A 2022; 126:5134-5147. [PMID: 35900106 DOI: 10.1021/acs.jpca.2c03387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We employed density functional theory (DFT)-based molecular dynamics simulations to explore the structure, dynamics, and spectral properties of the protic ionic entity trimethylammonium chloride (TMACl). Structural investigations include calculating the site-site radial distribution functions (RDFs), the distribution of constituent cations and anions in three-dimensional space, and combined distribution functions of the hydrogen-bonded pair RDF versus angle, revealing the structural characteristics of the ionic solvation and the intermolecular interactions within ions. Further, we determined the instantaneous vibrational stretching frequencies of the intrinsic N-H stretch probe modes by applying the time-series wavelet method. The associated ionic dynamics within the protic ionic compound were investigated by calculating the time-evolution of the fluctuating frequencies and the frequency-time correlation functions (FFCFs). The time scale related to the local structural relaxation process and the average hydrogen bond lifetime, ion cage dynamics, and mean squared displacement were investigated. The faster decay component of the FFCFs, depicting the intermolecular motion of intact hydrogen bonds in TMACl, is 0.07 ps for the Perdew-Burke-Ernzerhof (PBE)-based simulation and 0.06 ps for the PBE-D2 representation. The slower time scale of the longer picosecond decay time component of PBE and PBE-D2 representations are 3.13 and 2.87 ps, respectively. These picosecond time scales represent more significant fluctuations of the hydrogen-bonding partners in the ionic entity and hydrogen-bond jump events accompanied by large angular jumps. The longest picosecond time scales represent structural relaxation, including large angular jumps and ion-pair dynamics. Also, ion cage lifetimes correlate with the slowest time scale of the associated dynamics of vibrational spectral diffusion despite the type of DFT functional. This study benchmarks DFT treatments of the exchange-correlation functional with and without the van der Waals (vdW) dispersion correction scheme. The inclusion of vdW interactions to the PBE functional represents a less structured state of the ionic entity and faster dynamics of the molecular motions relative to the one predicted by the PBE system. All the results illustrate the necessity of accurately describing the Coulomb interactions, vdW dispersive interactive forces, and localized hydrogen bonds required to sustain the energetic balance in this ionic salt.
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Affiliation(s)
- Aritri Biswas
- Department of Chemistry, Indian Institute of Technology Hyderabad, Sangareddy 502284, Telangana, India
| | - Bhabani S Mallik
- Department of Chemistry, Indian Institute of Technology Hyderabad, Sangareddy 502284, Telangana, India
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Al-Mualem ZA, Baiz CR. Generative Adversarial Neural Networks for Denoising Coherent Multidimensional Spectra. J Phys Chem A 2022; 126:3816-3825. [PMID: 35668543 DOI: 10.1021/acs.jpca.2c02605] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Ultrafast spectroscopy often involves measuring weak signals and long data acquisition times. Spectra are typically collected as a "pump-probe" spectrum by measuring differences in intensity across laser shots. Shot-to-shot intensity fluctuations are most often the primary source of noise in ultrafast spectroscopy. Here, we present a novel approach for denoising ultrafast two-dimensional infrared (2D IR) spectra using conditional generative adversarial neural networks (cGANNs). The cGANN approach is able to eliminate shot-to-shot noise and reconstruct the line shapes present in the noisy input spectrum. We present a general approach for training the cGANN using matched pairs of noisy and clean synthetic 2D IR spectra based on the Kubo-line shape model for a three-level system. Experimental shot-to-shot laser noise is added to synthetic spectra to recreate the noise profile present in measured experimental spectra. The cGANNs can recover line shapes from synthetic 2D IR spectra with signal-to-noise ratios as low as 2:1, while largely preserving the key features such as center frequencies, line widths, and diagonal elongation. In addition, we benchmark the performance of the cGANN using experimental 2D IR spectra of an ester carbonyl vibrational probe and demonstrate that, by applying the cGANN denoising approach, we can extract the frequency-frequency time correlation function (FFCF) from reconstructed spectra using a nodal-line slope analysis. Finally, we provide a set of practical guidelines for extending the denoising method to other coherent multidimensional spectroscopies.
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Affiliation(s)
- Ziareena A Al-Mualem
- Department of Chemistry, University of Texas, Austin, Texas 78712, United States
| | - Carlos R Baiz
- Department of Chemistry, University of Texas, Austin, Texas 78712, United States
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Ikemoto Y, Harada Y, Tanaka M, Nishimura SN, Murakami D, Kurahashi N, Moriwaki T, Yamazoe K, Washizu H, Ishii Y, Torii H. Infrared Spectra and Hydrogen-Bond Configurations of Water Molecules at the Interface of Water-Insoluble Polymers under Humidified Conditions. J Phys Chem B 2022; 126:4143-4151. [PMID: 35639685 PMCID: PMC9189834 DOI: 10.1021/acs.jpcb.2c01702] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Elucidating the state of interfacial water, especially the hydrogen-bond configurations, is considered to be key for a better understanding of the functions of polymers that are exhibited in the presence of water. Here, an analysis in this direction is conducted for two water-insoluble biocompatible polymers, poly(2-methoxyethyl acrylate) and cyclic(poly(2-methoxyethyl acrylate)), and a non-biocompatible polymer, poly(n-butyl acrylate), by measuring their IR spectra under humidified conditions and by carrying out theoretical calculations on model complex systems. It is found that the OH stretching bands of water are decomposed into four components, and while the higher-frequency components (with peaks at ∼3610 and ∼3540 cm-1) behave in parallel with the C═O and C-O-C stretching and CH deformation bands of the polymers, the lower-frequency components (with peaks at ∼3430 and ∼3260 cm-1) become pronounced to a greater extent with increasing humidity. From the theoretical calculations, it is shown that the OH stretching frequency that is distributed from ∼3650 to ∼3200 cm-1 is correlated to the hydrogen-bond configurations and is mainly controlled by the electric field that is sensed by the vibrating H atom. By combining these observed and calculated results, the configurations of water at the interface of the polymers are discussed.
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Affiliation(s)
- Yuka Ikemoto
- Spectroscopy Division, Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan
| | - Yoshihisa Harada
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan.,Synchrotron Radiation Research Organization, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Masaru Tanaka
- Institute for Material Chemistry and Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.,Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Shin-Nosuke Nishimura
- Institute for Material Chemistry and Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Daiki Murakami
- Institute for Material Chemistry and Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.,Graduate School of Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Naoya Kurahashi
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan.,Synchrotron Radiation Research Organization, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Taro Moriwaki
- Spectroscopy Division, Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5198, Japan
| | - Kosuke Yamazoe
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan.,Synchrotron Radiation Research Organization, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Hitoshi Washizu
- Graduate School of Information Science, University of Hyogo, 7-1-28 Minatojima-Minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
| | - Yoshiki Ishii
- Graduate School of Information Science, University of Hyogo, 7-1-28 Minatojima-Minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
| | - Hajime Torii
- Department of Applied Chemistry and Biochemical Engineering, Faculty of Engineering, and Department of Optoelectronics and Nanostructure Science, Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561, Japan
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29
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Biswas A, Mallik BS. Vibrational Spectral Dynamics and Ion-Probe Interactions of the Hydrogen-Bonded Liquids in 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide. Chem Phys 2022. [DOI: 10.1016/j.chemphys.2022.111519] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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30
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Brünig FN, Geburtig O, Canal AV, Kappler J, Netz RR. Time-Dependent Friction Effects on Vibrational Infrared Frequencies and Line Shapes of Liquid Water. J Phys Chem B 2022; 126:1579-1589. [PMID: 35167754 PMCID: PMC8883462 DOI: 10.1021/acs.jpcb.1c09481] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
From ab initio simulations
of liquid water, the time-dependent
friction functions and time-averaged nonlinear effective bond potentials
for the OH stretch and HOH bend vibrations are extracted. The obtained
friction exhibits not only adiabatic contributions at and below the
vibrational time scales but also much slower nonadiabatic contributions,
reflecting homogeneous and inhomogeneous line broadening mechanisms,
respectively. Intermolecular interactions in liquid water soften both
stretch and bend potentials compared to the gas phase, which by itself
would lead to a red-shift of the corresponding vibrational bands.
In contrast, nonadiabatic friction contributions cause a spectral
blue shift. For the stretch mode, the potential effect dominates,
and thus, a significant red shift when going from gas to the liquid
phase results. For the bend mode, potential and nonadiabatic friction
effects are of comparable magnitude, so that a slight blue shift results,
in agreement with well-known but puzzling experimental findings. The
observed line broadening is shown to be roughly equally caused by
adiabatic and nonadiabatic friction contributions for both the stretch
and bend modes in liquid water. Thus, the quantitative analysis of
the time-dependent friction that acts on vibrational modes in liquids
advances the understanding of infrared vibrational frequencies and
line shapes.
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31
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Biswas A, Mallik BS. 2D IR spectra of the intrinsic vibrational probes of ionic liquid from dispersion corrected DFT-MD simulations. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.118390] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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32
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Das B, Chandra A. Ab Initio Molecular Dynamics Study of Aqueous Solutions of Magnesium and Calcium Nitrates: Hydration Shell Structure, Dynamics and Vibrational Echo Spectroscopy. J Phys Chem B 2022; 126:528-544. [PMID: 35001626 DOI: 10.1021/acs.jpcb.1c08545] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ab initio molecular dynamics simulations are performed to study the hydration shell structure, dynamics, and vibrational echo spectroscopy of aqueous Mg(NO3)2 and Ca(NO3)2 solutions. The hydration shell structure is probed through calculations of various ion-ion and ion-water radial and spatial distribution functions. On the dynamical side, calculations have been made for the hydrogen bond dynamics of hydration shells and also residence dynamics and lifetimes of water in different solvation environments. Subsequently, we looked at the dynamics of frequency fluctuations of OD modes of heavy water in different hydration environments. Specifically, the temporal decay of spectral observables of two-dimensional infrared (2DIR) spectroscopy, three pulse echo peak shift (3PEPS) measurements and also of time correlations of frequency fluctuations are calculated to investigate the dynamics of vibrational spectral diffusion of water in different hydration environments in these solutions. The OD stretch frequencies of water molecules in the vicinity of both divalent cations are found to be red-shifted and also fluctuating at a slower rate than other water molecules present in the solutions. The Mg2+ ions are found to be strongly hydrated which can be linked to their lower tendency to form contact ion-pairs and essentially no water exchange between the cationic hydration shells and bulk during the time scale of the current simulations. The stronger hydration of Mg2+ ions make their hydration shells structurally and dynamically more rigid and make the dynamics of hydrogen bonds and vibrational spectral diffusion, as revealed through spectral observables of 2DIR and 3PEPS slower than that for the Ca2+ ions. The structural and spectral dynamics of water molecules outside the cationic solvation shells in the Mg(NO3)2 solution are also found to be relatively slower than that of the Ca(NO3)2 solution and pure water which show the effects of stronger electric fields of Mg2+ ions extending beyond their first hydration shells. Also, water molecules in the hydration shells of the NO3- ions are found to relax at a slower rate in the Mg(NO3)2 solution which manifests the effect countercations have on anionic hydration shells for divalent metal nitrate solutions.
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Affiliation(s)
- Banshi Das
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India
| | - Amalendu Chandra
- Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur, Uttar Pradesh 208016, India
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33
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Biswas A, Mallik BS. Revisiting OD-stretching dynamics of methanol‑d4, ethanol-d6 and dilute HOD/H2O mixture with predefined potentials and wavelet transform spectra. Chem Phys 2022. [DOI: 10.1016/j.chemphys.2021.111385] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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34
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Cong Y, Zhai Y, Yang J, Grofe A, Gao J, Li H. Quantum vibration perturbation approach with polyatomic probe in simulating infrared spectra. Phys Chem Chem Phys 2021; 24:1174-1182. [PMID: 34932049 DOI: 10.1039/d1cp04490g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The quantitative prediction of vibrational spectra of chromophore molecules in solution is challenging and numerous methods have been developed. In this work, we present a quantum vibration perturbation (QVP) approach, which is a procedure that combines molecular quantum vibration and molecular dynamics with perturbation theory. In this framework, an initial Newtonian molecular dynamics simulation is performed, followed by a substitution process to embed molecular quantum vibrational wave functions into the trajectory. The instantaneous vibrational frequency shift at each time step is calculated using the Rayleigh-Schrödinger perturbation theory, where the perturbation operator is the difference in the vibrational potential between the reference chromophore and the perturbed chromophore in the environment. Semi-classical statistical mechanics is employed to obtain the spectral lineshape function. We validated our method using HCOOH·nH2O (n = 1-2) clusters and HCOOH aqueous solution as examples. The QVP method can be employed for rapid prediction of the vibrational spectrum of a specific mode in solution.
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Affiliation(s)
- Yang Cong
- Institute of Theoretical Chemistry, College of Chemistry, Jilin University, 2519 Jiefang Road, Changchun 130023, People's Republic of China.
| | - Yu Zhai
- Institute of Theoretical Chemistry, College of Chemistry, Jilin University, 2519 Jiefang Road, Changchun 130023, People's Republic of China.
| | - Jitai Yang
- Institute of Theoretical Chemistry, College of Chemistry, Jilin University, 2519 Jiefang Road, Changchun 130023, People's Republic of China.
| | - Adam Grofe
- Institute of Theoretical Chemistry, College of Chemistry, Jilin University, 2519 Jiefang Road, Changchun 130023, People's Republic of China.
| | - Jiali Gao
- Department of Chemistry and Supercomputing Institute, University of Minnesota, 207 Pleasant Street, SE, Minneapolis, MN 55455, USA. .,Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen 518055, China
| | - Hui Li
- Institute of Theoretical Chemistry, College of Chemistry, Jilin University, 2519 Jiefang Road, Changchun 130023, People's Republic of China.
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Abstract
Numerous linear and non-linear spectroscopic techniques have been developed to elucidate structural and functional information of complex systems ranging from natural systems, such as proteins and light-harvesting systems, to synthetic systems, such as solar cell materials and light-emitting diodes. The obtained experimental data can be challenging to interpret due to the complexity and potential overlapping spectral signatures. Therefore, computational spectroscopy plays a crucial role in the interpretation and understanding of spectral observables of complex systems. Computational modeling of various spectroscopic techniques has seen significant developments in the past decade, when it comes to the systems that can be addressed, the size and complexity of the sample types, the accuracy of the methods, and the spectroscopic techniques that can be addressed. In this Perspective, I will review the computational spectroscopy methods that have been developed and applied for infrared and visible spectroscopies in the condensed phase. I will discuss some of the questions that this has allowed answering. Finally, I will discuss current and future challenges and how these may be addressed.
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Affiliation(s)
- Thomas L C Jansen
- Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
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36
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Brünker P, Domenianni LI, Fleck N, Lindner J, Schiemann O, Vöhringer P. Intramolecular O-H⋯S hydrogen bonding in threefold symmetry: Line broadening dynamics from ultrafast 2DIR-spectroscopy and ab initio calculations. J Chem Phys 2021; 154:134305. [PMID: 33832237 DOI: 10.1063/5.0047885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The dynamics of intramolecular hydrogen-bonding involving sulfur atoms as acceptors is studied using two-dimensional infrared (2DIR) spectroscopy. The molecular system is a tertiary alcohol whose donating hydroxy group is embedded in a hydrogen-bond potential with torsional C3-symmetry about the carbon-oxygen bond. The linear and 2DIR-spectra recorded in the OH-stretching region of the alcohol can be simulated very well using Kubo's line shape theory based on the cumulant expansion for evaluating the linear and nonlinear optical response functions. The correlation function for OH-stretching frequency fluctuations reveals an ultrafast component decaying with a time constant of 700 fs, which is in line with the apparent decay of the center line slopes averaged over absorption and bleach/emission signals. In addition, a quasi-static inhomogeneity is detected, which prevents the 2DIR line shape to fully homogenize within the observation window of 4 ps. The experimental data were then analyzed in more detail using a full ab initio approach that merges time-dependent structural information from classical molecular dynamics (MD) simulations with an OH-stretching frequency map derived from density functional theory (DFT). The latter method was also used to obtain a complementary transition dipole map to account for non-Condon effects. The 2DIR-spectra obtained from the MD/DFT method are in good agreement with the experimental data at early waiting delays, thereby corroborating an assignment of the fast decay of the correlation function to the dynamics of hydrogen-bond breakage and formation.
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Affiliation(s)
- Paul Brünker
- Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße 12, 53115 Bonn, Germany
| | - Luis I Domenianni
- Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße 12, 53115 Bonn, Germany
| | - Nico Fleck
- Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße 12, 53115 Bonn, Germany
| | - Jörg Lindner
- Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße 12, 53115 Bonn, Germany
| | - Olav Schiemann
- Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße 12, 53115 Bonn, Germany
| | - Peter Vöhringer
- Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße 12, 53115 Bonn, Germany
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37
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Torii H, Ukawa R. Role of Intermolecular Charge Fluxes in the Hydrogen-Bond-Induced Frequency Shifts of the OH Stretching Mode of Water. J Phys Chem B 2021; 125:1468-1475. [PMID: 33506673 DOI: 10.1021/acs.jpcb.0c11461] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The relation between the vibrational properties and the electrostatic situations of the vibrating functional group is useful to predict vibrational spectroscopic features based on, for example, classical molecular dynamics of liquids or biomolecular systems, but to pursue its generality or the extent of applicability, it is required to understand the mechanisms giving rise to it. Here such an analysis is carried out for the OH stretching mode of water. By examining the correlations among various (structural, vibrational, and electrostatic) properties and by analyzing the spatial characteristics of the behavior of electrons occurring upon the vibration, it is shown that the dependence of the vibrational frequency and the dipole derivative of the OH stretching mode on the electric field is not of purely electrostatic origin, and the delocalized electronic motions occurring with this mode, called intermolecular charge fluxes, related to both the dipole first and second derivatives play important roles.
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Affiliation(s)
- Hajime Torii
- Department of Applied Chemistry and Biochemical Engineering, Faculty of Engineering, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561, Japan.,Department of Optoelectronics and Nanostructure Science, Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561, Japan
| | - Ryota Ukawa
- Department of Applied Chemistry and Biochemical Engineering, Faculty of Engineering, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu 432-8561, Japan
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38
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Efimov YY, Naberukhin YI. Coupling of three intramolecular vibration modes of liquid H 2O molecules in the framework of the fluctuation theory of hydrogen bonding. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 244:118772. [PMID: 32846302 DOI: 10.1016/j.saa.2020.118772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 06/30/2020] [Accepted: 07/16/2020] [Indexed: 06/11/2023]
Abstract
Vibrational spectra of liquid water contain a wealth of information about its structure and dynamics but there are no generally acknowledged interpretation of their band profiles, unfortunately. We have tried to calculate them taking into account only the coupling of three intramolecular vibrations in the set of H2O molecules with different initial oscillator frequencies and intensities. The matter is that each water molecule forms hydrogen bonds of different strengths; thus the OH stretching band spans several hundreds of wave numbers (the fluctuation theory of hydrogen bonding). This distribution overlaps with the similar band of the first overtone of the HOH bending frequencies thus triggering a Fermi resonance between three vibrations. There were some problems causing some simplifications in previous theoretical modeling of vibrational transitions in condensed water. To solve them we extract the statistical distribution of OH frequencies of H2O molecules directly from the experimental spectra of HOD molecules at the same conditions instead of defining it theoretically. Also the bending overtone is allowed to have non-zero intrinsic intensity when calculating the Fermi resonance. The test calculation of the isotropic component of the Raman spectrum which is most critical for interpretation shows that our algorithm can reproduces the characteristic peculiarities of the experiment. The spectrum consists of three non-Gaussian contours. The overtone of bending vibration, being strengthened by Fermi resonance, makes the greatest contribution to the dominating low-frequency spectrum component that was previously attributed to intermolecular coupling of adjacent OH oscillators by some authors. Further we plan to calculate similar band profiles in the IR and also Raman isotropic and anisotropic spectra of Н2О and D2О molecules within a wide temperature range for their quantitative comparison with experiment.
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Affiliation(s)
- Yu Ya Efimov
- Voevodsky Institute of Chemical Kinetics and Combustion, Siberian Branch of the Russian Academy of Science, Novosibirsk, Russia.
| | - Yu I Naberukhin
- Voevodsky Institute of Chemical Kinetics and Combustion, Siberian Branch of the Russian Academy of Science, Novosibirsk, Russia
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39
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Biswas A, Mallik BS. Ultrafast Aqueous Dynamics in Concentrated Electrolytic Solutions of Lithium Salt and Ionic Liquid. J Phys Chem B 2020; 124:9898-9912. [DOI: 10.1021/acs.jpcb.0c06221] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Aritri Biswas
- Department of Chemistry, Indian Institute of Technology Hyderabad, Sangareddy 502285, Telangana, India
| | - Bhabani S. Mallik
- Department of Chemistry, Indian Institute of Technology Hyderabad, Sangareddy 502285, Telangana, India
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40
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Baiz CR, Błasiak B, Bredenbeck J, Cho M, Choi JH, Corcelli SA, Dijkstra AG, Feng CJ, Garrett-Roe S, Ge NH, Hanson-Heine MWD, Hirst JD, Jansen TLC, Kwac K, Kubarych KJ, Londergan CH, Maekawa H, Reppert M, Saito S, Roy S, Skinner JL, Stock G, Straub JE, Thielges MC, Tominaga K, Tokmakoff A, Torii H, Wang L, Webb LJ, Zanni MT. Vibrational Spectroscopic Map, Vibrational Spectroscopy, and Intermolecular Interaction. Chem Rev 2020; 120:7152-7218. [PMID: 32598850 PMCID: PMC7710120 DOI: 10.1021/acs.chemrev.9b00813] [Citation(s) in RCA: 173] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Vibrational spectroscopy is an essential tool in chemical analyses, biological assays, and studies of functional materials. Over the past decade, various coherent nonlinear vibrational spectroscopic techniques have been developed and enabled researchers to study time-correlations of the fluctuating frequencies that are directly related to solute-solvent dynamics, dynamical changes in molecular conformations and local electrostatic environments, chemical and biochemical reactions, protein structural dynamics and functions, characteristic processes of functional materials, and so on. In order to gain incisive and quantitative information on the local electrostatic environment, molecular conformation, protein structure and interprotein contacts, ligand binding kinetics, and electric and optical properties of functional materials, a variety of vibrational probes have been developed and site-specifically incorporated into molecular, biological, and material systems for time-resolved vibrational spectroscopic investigation. However, still, an all-encompassing theory that describes the vibrational solvatochromism, electrochromism, and dynamic fluctuation of vibrational frequencies has not been completely established mainly due to the intrinsic complexity of intermolecular interactions in condensed phases. In particular, the amount of data obtained from the linear and nonlinear vibrational spectroscopic experiments has been rapidly increasing, but the lack of a quantitative method to interpret these measurements has been one major obstacle in broadening the applications of these methods. Among various theoretical models, one of the most successful approaches is a semiempirical model generally referred to as the vibrational spectroscopic map that is based on a rigorous theory of intermolecular interactions. Recently, genetic algorithm, neural network, and machine learning approaches have been applied to the development of vibrational solvatochromism theory. In this review, we provide comprehensive descriptions of the theoretical foundation and various examples showing its extraordinary successes in the interpretations of experimental observations. In addition, a brief introduction to a newly created repository Web site (http://frequencymap.org) for vibrational spectroscopic maps is presented. We anticipate that a combination of the vibrational frequency map approach and state-of-the-art multidimensional vibrational spectroscopy will be one of the most fruitful ways to study the structure and dynamics of chemical, biological, and functional molecular systems in the future.
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Affiliation(s)
- Carlos R. Baiz
- Department of Chemistry, University of Texas at Austin, Austin, TX 78712, U.S.A
| | - Bartosz Błasiak
- Department of Physical and Quantum Chemistry, Wroclaw University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
| | - Jens Bredenbeck
- Johann Wolfgang Goethe-University, Institute of Biophysics, Max-von-Laue-Str. 1, 60438, Frankfurt am Main, Germany
| | - Minhaeng Cho
- Center for Molecular Spectroscopy and Dynamics, Seoul 02841, Republic of Korea
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
| | - Jun-Ho Choi
- Department of Chemistry, Gwangju Institute of Science and Technology, Gwangju 61005, Republic of Korea
| | - Steven A. Corcelli
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556, U.S.A
| | - Arend G. Dijkstra
- School of Chemistry and School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, U.K
| | - Chi-Jui Feng
- Department of Chemistry, James Franck Institute and Institute for Biophysical Dynamics, University of Chicago, Chicago, IL 60637, U.S.A
| | - Sean Garrett-Roe
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, U.S.A
| | - Nien-Hui Ge
- Department of Chemistry, University of California at Irvine, Irvine, CA 92697-2025, U.S.A
| | - Magnus W. D. Hanson-Heine
- School of Chemistry, University of Nottingham, Nottingham, University Park, Nottingham, NG7 2RD, U.K
| | - Jonathan D. Hirst
- School of Chemistry, University of Nottingham, Nottingham, University Park, Nottingham, NG7 2RD, U.K
| | - Thomas L. C. Jansen
- University of Groningen, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG Groningen, The Netherlands
| | - Kijeong Kwac
- Center for Molecular Spectroscopy and Dynamics, Seoul 02841, Republic of Korea
| | - Kevin J. Kubarych
- Department of Chemistry, University of Michigan, 930 N. University Ave., Ann Arbor, MI 48109, U.S.A
| | - Casey H. Londergan
- Department of Chemistry, Haverford College, Haverford, Pennsylvania 19041, U.S.A
| | - Hiroaki Maekawa
- Department of Chemistry, University of California at Irvine, Irvine, CA 92697-2025, U.S.A
| | - Mike Reppert
- Chemical Physics Theory Group, Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Shinji Saito
- Department of Theoretical and Computational Molecular Science, Institute for Molecular Science, Myodaiji, Okazaki, 444-8585, Japan
| | - Santanu Roy
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6110, U.S.A
| | - James L. Skinner
- Institute for Molecular Engineering, University of Chicago, Chicago, IL 60637, U.S.A
| | - Gerhard Stock
- Biomolecular Dynamics, Institute of Physics, Albert Ludwigs University, 79104 Freiburg, Germany
| | - John E. Straub
- Department of Chemistry, Boston University, Boston, MA 02215, U.S.A
| | - Megan C. Thielges
- Department of Chemistry, Indiana University, 800 East Kirkwood, Bloomington, Indiana 47405, U.S.A
| | - Keisuke Tominaga
- Molecular Photoscience Research Center, Kobe University, Nada, Kobe 657-0013, Japan
| | - Andrei Tokmakoff
- Department of Chemistry, James Franck Institute and Institute for Biophysical Dynamics, University of Chicago, Chicago, IL 60637, U.S.A
| | - Hajime Torii
- Department of Applied Chemistry and Biochemical Engineering, Faculty of Engineering, and Department of Optoelectronics and Nanostructure Science, Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-Ku, Hamamatsu 432-8561, Japan
| | - Lu Wang
- Department of Chemistry and Chemical Biology, Institute for Quantitative Biomedicine, Rutgers University, 174 Frelinghuysen Road, Piscataway, NJ 08854, U.S.A
| | - Lauren J. Webb
- Department of Chemistry, The University of Texas at Austin, 105 E. 24th Street, STOP A5300, Austin, Texas 78712, U.S.A
| | - Martin T. Zanni
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706-1396, U.S.A
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41
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Lewis NHC, Iscen A, Felts A, Dereka B, Schatz GC, Tokmakoff A. Vibrational Probe of Aqueous Electrolytes: The Field Is Not Enough. J Phys Chem B 2020; 124:7013-7026. [DOI: 10.1021/acs.jpcb.0c05510] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Nicholas H. C. Lewis
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, United States
| | - Aysenur Iscen
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Alanna Felts
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Bogdan Dereka
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, United States
| | - George C. Schatz
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Andrei Tokmakoff
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, United States
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42
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Two-dimensional infrared spectroscopy of aqueous solutions from first principles simulations. Chem Phys Lett 2020. [DOI: 10.1016/j.cplett.2020.137493] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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43
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Rosa AS, Disalvo EA, Frias MA. Water Behavior at the Phase Transition of Phospholipid Matrixes Assessed by FTIR Spectroscopy. J Phys Chem B 2020; 124:6236-6244. [DOI: 10.1021/acs.jpcb.0c03719] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- A. S. Rosa
- Applied Biophysics and Food Research Center, National University of Santiago del Estero (CIBAAL-UNSE-CONICET), G4200 Santiago del Estero, Argentina
| | - E. A. Disalvo
- Applied Biophysics and Food Research Center, National University of Santiago del Estero (CIBAAL-UNSE-CONICET), G4200 Santiago del Estero, Argentina
| | - M. A. Frias
- Applied Biophysics and Food Research Center, National University of Santiago del Estero (CIBAAL-UNSE-CONICET), G4200 Santiago del Estero, Argentina
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44
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Bala AM, Killian WG, Plascencia C, Storer JA, Norfleet AT, Peereboom L, Jackson JE, Lira CT. Quantitative Analysis of Infrared Spectra of Binary Alcohol + Cyclohexane Solutions with Quantum Chemical Calculations. J Phys Chem A 2020; 124:3077-3089. [PMID: 32181659 DOI: 10.1021/acs.jpca.9b11245] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hydrogen bonding has profound effects on the behavior of molecules. Fourier-transform infrared spectroscopy is the technique most commonly used to qualitatively identify hydrogen-bonding moieties present in a chemical sample. However, quantitative analysis of infrared (IR) spectra is nontrivial for the hydroxyl stretching region where hydrogen bonding is most prominently expressed in organic alcohols and water. Specifically, the breadth and extreme overlap of the O-H stretching bands, and the order of magnitude variability of their IR attenuation coefficients complicates the analysis. In the present work, sequential molecular dynamics simulations and quantum mechanical calculations are used to develop a function to relate the integrated IR attenuation coefficient to the vibrational frequencies of hydroxyl bands across the O-H stretching region. This relationship is then used as a guide to develop an attenuation coefficient scaling function to quantitatively determine concentrations of alcohols in a hydrocarbon solution from experimental IR spectra by integration across the entire hydroxyl frequency range.
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Affiliation(s)
- Aseel M Bala
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, United States
| | - William G Killian
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, United States
| | - Cesar Plascencia
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Jackson A Storer
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, United States
| | - Andrew T Norfleet
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, United States
| | - Lars Peereboom
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, United States
| | - James E Jackson
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Carl T Lira
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, Michigan 48824, United States
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45
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Yamada SA, Hung ST, Thompson WH, Fayer MD. Effects of pore size on water dynamics in mesoporous silica. J Chem Phys 2020; 152:154704. [DOI: 10.1063/1.5145326] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- Steven A. Yamada
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | - Samantha T. Hung
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | - Ward H. Thompson
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
| | - Michael D. Fayer
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
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Kananenka AA, Strong SE, Skinner JL. Dephasing and Decoherence in Vibrational and Electronic Line Shapes. J Phys Chem B 2020; 124:1531-1542. [PMID: 31990552 DOI: 10.1021/acs.jpcb.9b11655] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Absorption and emission line shapes of vibrational and electronic transitions in liquids are broadened by interactions with the "bath" (in this case, the rotational and translational degrees of freedom of all the molecules in the liquid). If these degrees of freedom are treated classically, the broadening process is often known as dephasing. If, on the other hand, the bath degrees of freedom are instead treated quantum mechanically, there is additional broadening due to what is known in the chemical-physics literature as decoherence. The question addressed in this paper is the relative importance of decoherence (bath quantum effects) and dephasing. We present general developments of this subject for absorption and emission line shapes, discover several new relationships connecting classical and quantum treatments of the bath, and also consider the Stokes shift (difference in peak frequencies in absorption and emission). We next draw some general conclusions by considering a model system whose transition-frequency time-correlation function has only one bath time scale. We then consider a realistic system of the vibrational OH stretch transition of dilute HOD in liquid D2O at room temperature. For this system, we conclude that bath quantum effects are not very important, except for the Stokes shift. More generally, we argue that this is the case for many vibrational and most electronic transitions in room-temperature liquids.
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Affiliation(s)
- Alexei A Kananenka
- Pritzker School of Molecular Engineering , The University of Chicago , Chicago , Illinois 60637 , United States.,Department of Physics and Astronomy , University of Delaware , Newark , Delaware 19716 , United States
| | - Steven E Strong
- Pritzker School of Molecular Engineering , The University of Chicago , Chicago , Illinois 60637 , United States
| | - J L Skinner
- Pritzker School of Molecular Engineering , The University of Chicago , Chicago , Illinois 60637 , United States
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Priyadarshini A, Biswas A, Chakraborty D, Mallik BS. Structural and Thermophysical Anomalies of Liquid Water: A Tale of Molecules in the Instantaneous Low- and High-Density Regions. J Phys Chem B 2020; 124:1071-1081. [DOI: 10.1021/acs.jpcb.9b11596] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Adyasa Priyadarshini
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi-502285 Sangareddy, Telangana, India
| | - Aritri Biswas
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi-502285 Sangareddy, Telangana, India
| | - Debashree Chakraborty
- Department of Chemistry, National Institute of Technology Karnataka, Surathkal, 575025 Mangalore, Karnataka, India
| | - Bhabani S. Mallik
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi-502285 Sangareddy, Telangana, India
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Biswas A, Mallik BS. Distinctive behavior and two-dimensional vibrational dynamics of water molecules inside glycine solvation shell. RSC Adv 2020. [DOI: 10.1039/c9ra10521b] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We present a first principles molecular dynamics study of a deuterated aqueous solution of a single glycine moiety to explore the structure, dynamics, and two-dimensional infrared spectra of water molecules found in the solvation shell of glycine.
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Affiliation(s)
- Aritri Biswas
- Department of Chemistry
- Indian Institute of Technology Hyderabad
- Sangareddy
- India
| | - Bhabani S. Mallik
- Department of Chemistry
- Indian Institute of Technology Hyderabad
- Sangareddy
- India
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Roget SA, Kramer PL, Thomaz JE, Fayer MD. Bulk-like and Interfacial Water Dynamics in Nafion Fuel Cell Membranes Investigated with Ultrafast Nonlinear IR Spectroscopy. J Phys Chem B 2019; 123:9408-9417. [PMID: 31580076 DOI: 10.1021/acs.jpcb.9b07592] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The water confined in the hydrophilic domains of Nafion fuel cell membranes is central to its primary function of ion transport. Water dynamics are intimately linked to proton transfer and are sensitive to the structural features and length scales of confinement. Here, ultrafast polarization-selective pump-probe and two-dimensional infrared vibrational echo (2D IR) experiments were performed on fully hydrated Nafion membranes with sodium counterions to explicate the water dynamics. Like aerosol-OT reverse micelles (AOT RMs), the water dynamics in Nafion are attributed to bulk-like core water in the central region of the hydrophilic domains and much slower interfacial water. Population and orientational dynamics of water in Nafion are slowed by polymer confinement. Comparison of the observed dynamics to those of AOT RMs helps identify local interactions between water and sulfonate anions at the interface and among water molecules in the core. This comparison also demonstrates that the well-known spherical cluster morphology of Nafion is not appropriate. Spectral diffusion of the interfacial water, which arises from structural dynamics, was obtained from the 2D IR experiments taking the core water to have dynamics similar to bulk water. Like the orientational dynamics, spectral diffusion was found to be much slower at the interface compared to bulk water. Together, the dynamics indicate slow reorganization of weakly hydrogen-bonded water molecules at the interface of Nafion. These results provide insights into proton transport mechanisms in fuel cell membranes, and more generally, water dynamics near the interface of confining systems.
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Affiliation(s)
- Sean A Roget
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Patrick L Kramer
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Joseph E Thomaz
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Michael D Fayer
- Department of Chemistry , Stanford University , Stanford , California 94305 , United States
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Kananenka AA, Yao K, Corcelli SA, Skinner JL. Machine Learning for Vibrational Spectroscopic Maps. J Chem Theory Comput 2019; 15:6850-6858. [DOI: 10.1021/acs.jctc.9b00698] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Alexei A. Kananenka
- Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, United States
| | - Kun Yao
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Steven A. Corcelli
- Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - J. L. Skinner
- Pritzker School of Molecular Engineering, The University of Chicago, Chicago, Illinois 60637, United States
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