1
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Srivastava P, Elles CG. A Single-Shot Technique for Measuring Broadband Two-Photon Absorption Spectra in Solution. Anal Chem 2024; 96:11121-11125. [PMID: 38949250 DOI: 10.1021/acs.analchem.4c01656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Applications involving two-photon activation, including two-photon fluorescence imaging, photodynamic therapy, and 3D data storage, require precise knowledge of the two-photon absorption (2PA) spectra of target chromophores. Broadband pump-probe spectroscopy using femtosecond laser pulses provides wavelength-dependent 2PA spectra with absolute cross sections, but the measurements are sometimes complicated by cross-phase modulation effects and dispersion of the broadband probe. Here, we introduce a single-shot approach that eliminates artifacts from cross-phase modulation and enables more rapid measurements by avoiding the need to scan the time delay between the pump and the probe pulses. The approach uses counterpropagating beams to automatically integrate over the full interaction between the two pulses as they cross. We demonstrate this single-shot approach for a common 2PA reference, coumarin 153 (C153), in three different solvents using the output from a Yb:KGW laser. This approach provides accurate 2PA cross sections that are more reliable and easier to obtain compared with scanning pump-probe methods using copropagating laser beams. The single-shot method for broadband two-photon absorption (BB-2PA) spectroscopy also has significant advantages compared with single-wavelength measurements, such as z-scan and two-photon fluorescence.
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Affiliation(s)
- Prasenjit Srivastava
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Christopher G Elles
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
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2
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Sarangi R, Nanda KD, Krylov AI. Two- and one-photon absorption spectra of aqueous thiocyanate anion highlight the role of symmetry in the condensed phase. J Comput Chem 2024; 45:878-885. [PMID: 38156823 DOI: 10.1002/jcc.27282] [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: 09/26/2023] [Revised: 11/22/2023] [Accepted: 11/25/2023] [Indexed: 01/03/2024]
Abstract
We present the two-photon absorption (2PA) spectrum of aqueous thiocyanate calculated using high-level quantum-chemistry methods. The 2PA spectrum is compared to the one-photon absorption (1PA) spectrum computed using the same computational protocol. Although the two spectra probe the same set of electronic states, the intensity patterns are different, leading to an apparent red-shift of the 2PA spectrum relative to the 1PA spectrum. The presented analysis explains the intensity patterns and attributes the differences between the 1PA and 2PA spectra to the native symmetry of isolated SCN - , which influences the spectra in the low-symmetry solvated environment. The native symmetry also manifests itself in variations of the polarization ratio (e.g., parallel vs. perpendicular cross sections) across the spectrum. The presented results highlight the potential of 2PA spectroscopy and high-level quantum-chemistry methods in studies of condensed-phase phenomena.
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Affiliation(s)
- Ronit Sarangi
- Department of Chemistry, University of Southern California, Los Angeles, California, USA
| | - Kaushik D Nanda
- Department of Chemistry, University of Southern California, Los Angeles, California, USA
| | - Anna I Krylov
- Department of Chemistry, University of Southern California, Los Angeles, California, USA
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3
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Michon MA, Chmielniak P, Weber PM, Rose-Petruck C. Two-photon chemistry of tetrahydrofuran in clathrate hydrates. Phys Chem Chem Phys 2024; 26:2568-2579. [PMID: 38170862 DOI: 10.1039/d3cp02607h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
High-lying electronic states hold the potential for new and unusual photochemical reactions. However, for conventional single-photon excitation in the condensed phase, reaching these states is often not possible because the vacuum-ultraviolet (VUV) light required is competitively absorbed by the surrounding matrix rather than the molecule of interest. Here, this hurdle is overcome by leveraging nonresonant two-photon absorption (2PA) at 265 nm to achieve preferential photolysis of tetrahydrofuran (THF) trapped within a clathrate hydrate network at 77 K. Electron spin resonance (ESR) spectroscopy enables direct observation and identification of otherwise short-lived organic radicals stabilized by the clathrate cages, providing clues into the rapid dynamics that immediately follow photoexcitation. 2PA induces extensive fragmentation of enclathrated THF yielding 1-alkyl, acyl, allyl and methyl radicals-a stark departure from the reactive motifs commonly reported in γ-irradiated hydrates. We speculate on the undetected transient dynamics and explore the potential role of trapped electrons generated from water and THF. This demonstration of nonresonant two-photon chemistry presents an alternative approach to targeted condensed phase photochemistry in the VUV energy range.
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Affiliation(s)
- Michael A Michon
- Department of Chemistry, Brown University, Providence, 02912, Rhode Island, USA.
| | - Pawel Chmielniak
- Department of Chemistry, Brown University, Providence, 02912, Rhode Island, USA.
| | - Peter M Weber
- Department of Chemistry, Brown University, Providence, 02912, Rhode Island, USA.
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4
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Srivastava P, Stierwalt DA, Elles CG. Broadband Two-Photon Absorption Spectroscopy with Stimulated Raman Scattering as an Internal Standard. Anal Chem 2023; 95:13227-13234. [PMID: 37603818 PMCID: PMC10484208 DOI: 10.1021/acs.analchem.3c02298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 08/10/2023] [Indexed: 08/23/2023]
Abstract
Two-photon absorption (2PA) spectroscopy provides valuable information about the nonlinear properties of molecules. In contrast with single-wavelength methods, broadband 2PA spectroscopy using a pump-probe approach gives a continuous 2PA spectrum across a wide range of transition energies without tuning the excitation laser. This contribution shows how stimulated Raman scattering from the solvent can be used as a convenient and robust internal standard for obtaining accurate absolute 2PA cross sections using the broadband approach. Stimulated Raman scattering has the same pump-probe overlap dependence as 2PA, thus eliminating the need to measure the intensity-dependent overlap of the pump and probe directly. Eliminating the overlap represents an important improvement because intensity profiles are typically the largest source of uncertainty in the measurement of absolute 2PA cross sections using any method. Raman scattering cross sections are a fundamental property of the solvent and therefore provide a universal standard that can be applied any time the 2PA and Raman signals are present within the same probe wavelength range. We demonstrate this approach using sample solutions of coumarin 153 in methanol, DMSO, and toluene, as well as fluorescein in water.
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Affiliation(s)
- Prasenjit Srivastava
- Department of Chemistry, University
of Kansas, Lawrence, Kansas 66045, United States
| | - David A. Stierwalt
- Department of Chemistry, University
of Kansas, Lawrence, Kansas 66045, United States
| | - Christopher G. Elles
- Department of Chemistry, University
of Kansas, Lawrence, Kansas 66045, United States
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5
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Thøgersen J, Weidner T, Jensen F. The primary photolysis of aqueous carbonate di-anions. Phys Chem Chem Phys 2023; 25:14104-14116. [PMID: 37161877 DOI: 10.1039/d3cp00236e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We study the primary photolysis dynamics of aqueous carbonate, CO32-(aq), and hydrogen carbonate, HCO3-(aq), when they are excited at λ = 200 nm. The photolysis is recorded with sub-picosecond time resolution using UV pump-Vis probe and UV pump-IR probe transient absorption spectroscopy and interpreted with the aid of density functional theory calculations. When CO32- is excited via single photon absorption at λ = 200 nm, Φ(t = 20 ps) = 82 ± 5% of the excited di-anions either detach an electron or dissociate. The electron detachment takes place from the excited state in t < 1 ps and forms ground state CO3˙- and eaq-. Dissociation occurs from both the electronic ground and excited states of CO32-. Dissociation from the CO32- excited state is assisted by water molecules and forms CO2˙-, OH˙ and OH-. The dissociation occurs both directly from the Franck-Condon region in t < 1 ps and indirectly with a time constant of τ = 13.9 ± 0.5 ps as the excited state relaxes. Dissociation of vibrationally excited CO32- molecules in the electronic ground state is also assisted by water molecules and forms CO2 and two OH- anions. The dissociation and subsequent vibrational relaxation of CO2 occur with a time constant of τ = 10.2 ± 0.5 ps. The residual 1 - Φ(t = 20 ps) = 18 ± 5% of the excited CO32- di-anions return by internal conversion to the equilibrated CO32- ground state with a time constant of τ = 4.0 ± 0.4 ps. The extinction coefficient of aqueous hydrogen carbonate HCO3-(aq) at λ = 200 nm is an order of magnitude smaller than that of carbonate, so even though the hydrogen carbonate anions dominate the carbonate di-anions in the hydrogen carbonate solution, the primary photolysis of hydrogen carbonate is obscured by the photo-products of carbonate. Hence, we are unable to assess the primary photolysis of hydrogen carbonate. However, the weak one-photon absorption facilitates two-photon ionization of water, which forms hydronium, H3O+, cations. The sudden increase in the acidity induced by two-photon ionization protonates the ground state hydrogen carbonate molecules, thus offering a rare spectroscopic glimpse of aqueous carbonic acid.
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Affiliation(s)
- Jan Thøgersen
- Department of Chemistry, Aarhus University. Langelandsgade 140, DK-8000 Aarhus C, Denmark.
| | - Tobias Weidner
- Department of Chemistry, Aarhus University. Langelandsgade 140, DK-8000 Aarhus C, Denmark.
| | - Frank Jensen
- Department of Chemistry, Aarhus University. Langelandsgade 140, DK-8000 Aarhus C, Denmark.
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6
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Song Z, Ge C, Song Y, Chen Z, Shao B, Yuan X, Chen J, Xu D, Song T, Fang J, Wang Y, Sun B. Synergistic Solar-Driven Freshwater Generation and Electricity Output Empowered by Wafer-Scale Nanostructured Silicon. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2205265. [PMID: 36420652 DOI: 10.1002/smll.202205265] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 10/29/2022] [Indexed: 06/16/2023]
Abstract
Electricity generation triggered by the ubiquitous water evaporation process provides an intriguing way to harvest energy from water. Meanwhile, natural water evaporation is also a fundamental way to obtain fresh water for human beings. Here, a wafer-scale nanostructured silicon-based device that takes advantage of its well-aligned configuration that simultaneously realizes solar steam generation (SSG) for freshwater collection and hydrovoltaic effect generation for electricity output is developed. An ingenious porous, black carbon nanotube fabric (CNF) electrode endows the device with sustainable water self-pumping capability, excellent durable conductivity, and intense solar spectrum harvesting. A combined device based on the CNF electrode integrated with nanostructured silicon nanowire arrays (SiNWs) provided an aligned numerous surface-to-volume water evaporation interface that enables a recorded continuous short-circuit current 8.65 mA and a water evaporation rate of 1.31 kg m-2 h-1 under one sun illumination. Such wafer-scale SiNWs-based SSG and hydrovoltaic integration devices would unchain the bottleneck of the weak and discontinuous electrical output of hydrovoltaic devices, which inspires other sorts of semiconductor-based hydrovoltaic device designs to target superior performance.
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Affiliation(s)
- Zheheng Song
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Can Ge
- College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, P. R. China
| | - Yuhang Song
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Zhewei Chen
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Beibei Shao
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Xianrong Yuan
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Jiangyu Chen
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Duo Xu
- College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, P. R. China
| | - Tao Song
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
| | - Jian Fang
- College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, P. R. China
| | - Yusheng Wang
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Macao Institute of Materials Science and Engineering (MIMSE), MUST-SUDA Joint Research Center for Advanced Functional Materials, Macau University of Science and Technology, Taipa, Macau SAR, 999078, P. R. China
| | - Baoquan Sun
- Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, Jiangsu, 215123, P. R. China
- Macao Institute of Materials Science and Engineering (MIMSE), MUST-SUDA Joint Research Center for Advanced Functional Materials, Macau University of Science and Technology, Taipa, Macau SAR, 999078, P. R. China
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7
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Abstract
Knowledge of the electronic structure of an aqueous solution is a prerequisite to understanding its chemical and biological reactivity and its response to light. One of the most direct ways of determining electronic structure is to use photoelectron spectroscopy to measure electron binding energies. Initially, photoelectron spectroscopy was restricted to the gas or solid phases due to the requirement for high vacuum to minimize inelastic scattering of the emitted electrons. The introduction of liquid-jets and their combination with intense X-ray sources at synchrotrons in the late 1990s expanded the scope of photoelectron spectroscopy to include liquids. Liquid-jet photoelectron spectroscopy is now an active research field involving a growing number of research groups. A limitation of X-ray photoelectron spectroscopy of aqueous solutions is the requirement to use solutes with reasonably high concentrations in order to obtain photoelectron spectra with adequate signal-to-noise after subtracting the spectrum of water. This has excluded most studies of organic molecules, which tend to be only weakly soluble. A solution to this problem is to use resonance-enhanced photoelectron spectroscopy with ultraviolet (UV) light pulses (hν ≲ 6 eV). However, the development of UV liquid-jet photoelectron spectroscopy has been hampered by a lack of quantitative understanding of inelastic scattering of low kinetic energy electrons (≲5 eV) and the impact on spectral lineshapes and positions.In this Account, we describe the key steps involved in the measurement of UV photoelectron spectra of aqueous solutions: photoionization/detachment, electron transport of low kinetic energy electrons through the conduction band, transmission through the water-vacuum interface, and transport through the spectrometer. We also explain the steps we take to record accurate UV photoelectron spectra of liquids with excellent signal-to-noise. We then describe how we have combined Monte Carlo simulations of electron scattering and spectral inversion with molecular dynamics simulations of depth profiles of organic solutes in aqueous solution to develop an efficient and widely applicable method for retrieving true UV photoelectron spectra of aqueous solutions. The huge potential of our experimental and spectral retrieval methods is illustrated using three examples. The first is a measurement of the vertical detachment energy of the green fluorescent protein chromophore, a sparingly soluble organic anion whose electronic structure underpins its fluorescence and photooxidation properties. The second is a measurement of the vertical ionization energy of liquid water, which has been the subject of discussion since the first X-ray photoelectron spectroscopy measurement in 1997. The third is a UV photoelectron spectroscopy study of the vertical ionization energy of aqueous phenol which demonstrates the possibility of retrieving true photoelectron spectra from measurements with contributions from components with different concentration profiles.
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8
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Scholz M, Fortune WG, Tau O, Fielding HH. Accurate Vertical Ionization Energy of Water and Retrieval of True Ultraviolet Photoelectron Spectra of Aqueous Solutions. J Phys Chem Lett 2022; 13:6889-6895. [PMID: 35862937 PMCID: PMC9358712 DOI: 10.1021/acs.jpclett.2c01768] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 07/14/2022] [Indexed: 05/23/2023]
Abstract
Ultraviolet (UV) photoelectron spectroscopy provides a direct way of measuring valence electronic structure; however, its application to aqueous solutions has been hampered by a lack of quantitative understanding of how inelastic scattering of low-energy (<5 eV) electrons in liquid water distorts the measured electron kinetic energy distributions. Here, we present an efficient and widely applicable method for retrieving true UV photoelectron spectra of aqueous solutions. Our method combines Monte Carlo simulations of electron scattering and spectral inversion, with molecular dynamics simulations of depth profiles of organic solutes in aqueous solution. Its application is demonstrated for both liquid water, and aqueous solutions of phenol and phenolate, which are ubiquitous biologically relevant structural motifs.
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Affiliation(s)
- Michael
S. Scholz
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - William G. Fortune
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - Omri Tau
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - Helen H. Fielding
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
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9
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Bhattacharyya D, Zhang Y, Elles CG, Bradforth SE. Electronic Structure of Liquid Alkanes: A Representative Case of Liquid Hexanes and Cyclohexane Studied Using Polarization-Dependent Two-Photon Absorption Spectroscopy. J Phys Chem A 2021; 125:7988-7999. [PMID: 34478284 DOI: 10.1021/acs.jpca.1c06230] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Two-photon absorption (2PA) spectra of liquid cyclohexane and hexanes are reported for the energy range 6.4-8.5 eV (177-145 nm), providing detailed information about their electronic structures in bulk liquid. Using a broadband pump-probe fashion, we measured the continuous 2PA spectra by simultaneous absorption of a 266 nm (4.6 eV) pump photon and one UV-vis probe photon from the white-light continuum (1.8-3.9 eV). Theoretical one-photon absorption (1PA) and 2PA cross sections of isolated gas phase molecules are computed by the equation of motion coupled-cluster method with single and double substitutions (EOM-CCSD) to substantiate the assignment of the experimental spectra, and the natural transition orbital (NTO) analysis provides visualization of the participating orbitals in a transition. Our analysis suggests that upon solvation transitions at the lowest excitation energy involving promotion of electron to the 3s Rydberg orbitals are blue-shifted (∼0.55 eV for cyclohexane and ∼0.18 eV for hexanes) to a greater extent as compared to those involving other Rydberg orbitals, which is similar to the behavior observed for water and alcohols. All other transitions experience negligible (cyclohexane) or minor red-shift by ∼0.15-0.2 eV (hexane) upon solvation. In both alkanes, the spectra are entirely dominated by Rydberg transitions: the most intense bands in 1PA and 2PA spectra are due to the excitation of electrons to the Rydberg "p" and "d" type orbitals, respectively, although one transition terminating in the 3s Rydberg has significant 2PA strength. This work demonstrates that the gas phase electronic transition properties in alkanes are not significantly altered upon solvation. In addition, electronic structure calculations using an isolated-molecule framework appear to provide a reasonable starting point for a semiquantitative picture for spectral assignment and also to analyze the solvatochromic shifts for liquid phase absorption spectra.
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Affiliation(s)
- Dhritiman Bhattacharyya
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | - Yuyuan Zhang
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | - Christopher G Elles
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | - Stephen E Bradforth
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
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10
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Burns KH, Srivastava P, Elles CG. Absolute Cross Sections of Liquids from Broadband Stimulated Raman Scattering with Femtosecond and Picosecond Pulses. Anal Chem 2020; 92:10686-10692. [PMID: 32598135 DOI: 10.1021/acs.analchem.0c01785] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Broadband stimulated Raman scattering (SRS) is often observed in applications that use nonlinear spectroscopy to probe the composition or dynamics of complex systems. Whether the SRS response is measured intentionally or unintentionally, as a background signal, the relative scattering intensities provide a quantitative measure of the population profile of target molecules. Solvent scattering is a valuable internal reference for determining absolute concentrations in these applications, but accurate cross sections have been reported for only a limited number of transitions in select solvents and were measured using spontaneous Raman scattering with narrowband continuous wave or nanosecond light sources. This work reports the measurement and analysis of absolute Raman scattering cross sections spanning the frequency range of 500-4000 cm-1 for cyclohexane, DMSO, acetonitrile, methanol, water, benzene, and toluene using broadband SRS with femtosecond and picosecond Raman pump pulses at 488 nm. Varying the duration of the Raman pump pulses from ∼80 fs to >1 ps confirms that the cross sections are independent of the spectral bandwidth across the range of ∼250 to <20 cm-1. The cross sections and depolarization ratios measured using broadband SRS agree with the limited number of previously reported values, after accounting for overlapping transitions in the lower-resolution femtosecond and picosecond spectra. The SRS cross sections reported here can be used with confidence as internal reference standards for a wide range of applications, including nonlinear spectroscopy and coherent microscopy measurements using ultrafast lasers.
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Affiliation(s)
- Kristen H Burns
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Prasenjit Srivastava
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Christopher G Elles
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
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11
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Yamamoto YI, Suzuki T. Ultrafast Dynamics of Water Radiolysis: Hydrated Electron Formation, Solvation, Recombination, and Scavenging. J Phys Chem Lett 2020; 11:5510-5516. [PMID: 32551690 DOI: 10.1021/acs.jpclett.0c01468] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The ultrafast formation, solvation, and geminate recombination of hydrated electrons upon vacuum ultraviolet photoexcitation of liquid water and the static and dynamic scavenging by NO3- are investigated using femtosecond time-resolved photoelectron spectroscopy. The solvation time constant for excess electrons is typical of that for liquid water but increases slightly with increasing excitation energy. The electron survival probability for geminate recombination is found to be much lower than the literature values owing to previously unobserved ultrafast geminate recombination in a period of 5 ps. NO3- induces the ultrafast (static) scavenging of photoexcited electronic states of liquid water and the dynamic scavenging of detached electrons with a reaction rate that is dependent on the excitation energy. The formation of hydrated electrons at 7.7 eV is ascribed to a H-atom-transfer process, but it is plausible that additional formation channels open at higher energies.
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Affiliation(s)
- Yo-Ichi Yamamoto
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - Toshinori Suzuki
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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12
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Bhattacharyya D, Mizuno H, Rizzuto AM, Zhang Y, Saykally RJ, Bradforth SE. New Insights into the Charge-Transfer-to-Solvent Spectrum of Aqueous Iodide: Surface versus Bulk. J Phys Chem Lett 2020; 11:1656-1661. [PMID: 32040333 DOI: 10.1021/acs.jpclett.9b03857] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Liquid phase charge-transfer-to-solvent (CTTS) transitions are important, as they serve as photochemical routes to solvated electrons. In this work, broadband deep-ultraviolet electronic sum frequency generation (DUV-ESFG) and two-photon absorption (2PA) spectroscopic techniques were used to assign and compare the nature of the aqueous iodide CTTS excitations at the air/water interface and in bulk solution. In the one-photon absorption (1PA) spectrum, excitation to the 6s Rydberg-like orbital (5p → 6s) gives rise to a pair of spin-orbit split iodine states, 2P3/2 and 2P1/2. In the 2PA spectra, the lower-energy 2P3/2 peak is absent and the observed 2PA peak, which is ∼0.14 eV blue-shifted relative to the upper 2P1/2 CTTS peak seen in 1PA, arises from 5p → 6p electronic promotion. The band observed in the ESFG spectrum is attributed to mixing of excited states involving 5p → 6p and 5p → 6s promotions caused by both vibronic coupling and the external electric field generated by asymmetric interfacial solvation.
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Affiliation(s)
- Dhritiman Bhattacharyya
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Hikaru Mizuno
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Anthony M Rizzuto
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Yuyuan Zhang
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
| | - Richard J Saykally
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Stephen E Bradforth
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
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13
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Bhattacharyya D, Zhang Y, Elles CG, Bradforth SE. Electronic Structure of Liquid Methanol and Ethanol from Polarization-Dependent Two-Photon Absorption Spectroscopy. J Phys Chem A 2019; 123:5789-5804. [DOI: 10.1021/acs.jpca.9b04040] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Dhritiman Bhattacharyya
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | - Yuyuan Zhang
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | - Christopher G. Elles
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | - Stephen E. Bradforth
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
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14
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Pohl MN, Muchová E, Seidel R, Ali H, Sršeň Š, Wilkinson I, Winter B, Slavíček P. Do water's electrons care about electrolytes? Chem Sci 2019; 10:848-865. [PMID: 30774880 PMCID: PMC6346409 DOI: 10.1039/c8sc03381a] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 11/01/2018] [Indexed: 01/01/2023] Open
Abstract
Ions have a profound effect on the geometrical structure of liquid water and an aqueous environment is known to change the electronic structure of ions. Here we combine photoelectron spectroscopy measurements from liquid microjets with molecular dynamical and quantum chemical calculations to address the reverse question, to what extent do ions affect the electronic structure of liquid water? We study aqueous solutions of sodium iodide (NaI) over a wide concentration range, from nearly pure water to 8 M solutions, recording spectra in the 5 to 60 eV binding energy range to include all water valence and the solute Na+ 2p, I- 4d, and I- 5p orbital ionization peaks. We observe that the electron binding energies of the solute ions change only slightly as a function of electrolyte concentration, less than 150 ± 60 meV over an ∼8 M range. Furthermore, the photoelectron spectrum of liquid water is surprisingly mildly affected as we transform the sample from a dilute aqueous salt solution to a viscous, crystalline-like phase. The most noticeable spectral changes are a negative binding energy shift of the water 1b2 ionizing transition (up to -370 ± 60 meV) and a narrowing of the flat-top shape water 3a1 ionization feature (up to 450 ± 90 meV). A novel computationally efficient technique is introduced to calculate liquid-state photoemission spectra using small clusters from molecular dynamics (MD) simulations embedded in dielectric continuum. This theoretical treatment captured the characteristic positions and structures of the aqueous photoemission peaks, reproducing the experimentally observed narrowing of the water 3a1 feature and weak sensitivity of the water binding energies to electrolyte concentration. The calculations allowed us to attribute the small binding energy shifts to ion-induced disruptions of intermolecular electronic interactions. Furthermore, they demonstrate the importance of considering concentration-dependent screening lengths for a correct description of the electronic structure of solvated systems. Accounting for electronic screening, the calculations highlight the minimal effect of electrolyte concentration on the 1b1 binding energy reference, in accord with the experiments. This leads us to a key finding that the isolated, lowest-binding-energy, 1b1, photoemission feature of liquid water is a robust energetic reference for aqueous liquid microjet photoemission studies.
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Affiliation(s)
- Marvin N Pohl
- Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , D-14195 Berlin , Germany .
- Fachbereich Physik , Freie Universität Berlin , Arnimallee 14 , D-14195 Berlin , Germany
| | - Eva Muchová
- Department of Physical Chemistry , University of Chemistry and Technology , Technická 5 , 16628 Prague , Czech Republic .
| | - Robert Seidel
- Helmholtz-Zentrum Berlin für Materialien und Energie , Hahn-Meitner-Platz 1 , D-14109 Berlin , Germany .
- Humboldt-Universität zu Berlin , Department of Chemistry , Brook-Taylor-Str. 2 , D-12489 Berlin , Germany
| | - Hebatallah Ali
- Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , D-14195 Berlin , Germany .
- Fachbereich Physik , Freie Universität Berlin , Arnimallee 14 , D-14195 Berlin , Germany
| | - Štěpán Sršeň
- Department of Physical Chemistry , University of Chemistry and Technology , Technická 5 , 16628 Prague , Czech Republic .
| | - Iain Wilkinson
- Helmholtz-Zentrum Berlin für Materialien und Energie , Hahn-Meitner-Platz 1 , D-14109 Berlin , Germany .
| | - Bernd Winter
- Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , D-14195 Berlin , Germany .
| | - Petr Slavíček
- Department of Physical Chemistry , University of Chemistry and Technology , Technická 5 , 16628 Prague , Czech Republic .
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15
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de Wergifosse M, Houk AL, Krylov AI, Elles CG. Two-photon absorption spectroscopy of trans-stilbene, cis-stilbene, and phenanthrene: Theory and experiment. J Chem Phys 2018; 146:144305. [PMID: 28411609 DOI: 10.1063/1.4979651] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Two-photon absorption (2PA) spectroscopy provides complementary, and sometimes more detailed, information about the electronic structure of a molecule relative to one-photon absorption (1PA) spectroscopy. However, our understanding of the 2PA processes is rather limited due to technical difficulties in measuring experimental 2PA spectra and theoretical challenges in computing higher-order molecular properties. This paper examines the 2PA spectroscopy of trans-stilbene, cis-stilbene, and phenanthrene by a combined experimental and theoretical approach. The broadband 2PA spectra of all three compounds are measured under identical conditions in order to facilitate a direct comparison of the absolute 2PA cross sections in the range 3.5-6.0 eV. For comparison, the theoretical 2PA cross sections are computed using the equation-of-motion coupled-cluster method with single and double substitutions. Simulated 2PA spectra based on the calculations reproduce the main features of the experimental spectra in solution, although the quantitative comparison is complicated by a number of uncertainties, including limitations of the theoretical model, vibronic structure, broadening of the experimental spectra, and solvent effects. The systematic comparison of experimental and theoretical spectra for this series of structurally similar compounds provides valuable insight into the nature of 2PA transitions in conjugated molecules. Notably, the orbital character and symmetry-based selection rules provide a foundation for interpreting the features of the experimental 2PA spectra in unprecedented detail.
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Affiliation(s)
- Marc de Wergifosse
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, USA
| | - Amanda L Houk
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, USA
| | - Anna I Krylov
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, USA
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16
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Roy A, Seidel R, Kumar G, Bradforth SE. Exploring Redox Properties of Aromatic Amino Acids in Water: Contrasting Single Photon vs Resonant Multiphoton Ionization in Aqueous Solutions. J Phys Chem B 2018. [DOI: 10.1021/acs.jpcb.7b11762] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anirban Roy
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | - Robert Seidel
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
- Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany
| | - Gaurav Kumar
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | - Stephen E. Bradforth
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
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17
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Gaiduk AP, Pham TA, Govoni M, Paesani F, Galli G. Electron affinity of liquid water. Nat Commun 2018; 9:247. [PMID: 29339731 PMCID: PMC5770385 DOI: 10.1038/s41467-017-02673-z] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 12/15/2017] [Indexed: 11/09/2022] Open
Abstract
Understanding redox and photochemical reactions in aqueous environments requires a precise knowledge of the ionization potential and electron affinity of liquid water. The former has been measured, but not the latter. We predict the electron affinity of liquid water and of its surface from first principles, coupling path-integral molecular dynamics with ab initio potentials, and many-body perturbation theory. Our results for the surface (0.8 eV) agree well with recent pump-probe spectroscopy measurements on amorphous ice. Those for the bulk (0.1-0.3 eV) differ from several estimates adopted in the literature, which we critically revisit. We show that the ionization potential of the bulk and surface are almost identical; instead their electron affinities differ substantially, with the conduction band edge of the surface much deeper in energy than that of the bulk. We also discuss the significant impact of nuclear quantum effects on the fundamental gap and band edges of the liquid.
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Affiliation(s)
- Alex P Gaiduk
- Institute for Molecular Engineering, The University of Chicago, Chicago, IL, 60637, USA
| | - Tuan Anh Pham
- Lawrence Livermore National Laboratory, Livermore, CA, 94551, USA
| | - Marco Govoni
- Institute for Molecular Engineering, The University of Chicago, Chicago, IL, 60637, USA.,Materials Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Francesco Paesani
- Department of Chemistry and Biochemistry, Materials Science and Engineering, San Diego Supercomputer Center, University of California, San Diego, 92093, USA.
| | - Giulia Galli
- Institute for Molecular Engineering, The University of Chicago, Chicago, IL, 60637, USA. .,Materials Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA.
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18
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Vogler T, Vöhringer P. Probing the band gap of liquid ammonia with femtosecond multiphoton ionization spectroscopy. Phys Chem Chem Phys 2018; 20:25657-25665. [DOI: 10.1039/c8cp05030a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The solvated electron primary yield is used in a multiphoton-ionization action-spectroscopic experiment to explore the band gap of liquid ammonia.
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Affiliation(s)
- Tim Vogler
- Institut für Physikalische und Theoretische Chemie
- Rheinische Friedrich-Wilhelms-Universität
- 53115 Bonn
- Germany
| | - Peter Vöhringer
- Institut für Physikalische und Theoretische Chemie
- Rheinische Friedrich-Wilhelms-Universität
- 53115 Bonn
- Germany
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19
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Guan J, Daljeet R, Song Y. Pressure-selected reactivity between 2-butyne and water induced by two-photon excitation. CAN J CHEM 2017. [DOI: 10.1139/cjc-2017-0155] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
High-pressure photochemistry between 2-butyne (H3CC≡CCH3) and trace amount of H2O was investigated at room temperature using multiline UV radiation at λ ≈ 350 nm and monitored by FTIR spectroscopy. Instead of the expected polymerization of 2-butyne, the IR spectral analysis suggests the formation of cis- and trans-2-butene, as well as 2-butanone, as the primary products. The possible reaction mechanisms and production pathways of these products were examined, where the dissociation of water molecule as the other reactant is believed as the essential step of the photochemical reaction. We further found that initial loading pressure of the mixture can not only substantially influence the reaction kinetics, but also regulate the accessibilities to some reaction channels, which was evidenced by quantitative analysis of the characteristic IR bands of 2-butene and 2-butanone. The relative abundance of two products is found to be highly dependent on pressure and radiation time. This study provides attractive physical routes in the absence of solvents, catalysts, and radical initiators, to synthesis the relevant products with a great selectivity and feasibility.
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Affiliation(s)
- Jiwen Guan
- Department of Physics and Astronomy, University of Western Ontario, London, ON N6A 3K7, Canada
| | - Roshan Daljeet
- Department of Chemistry, University of Western Ontario, London, ON N6A 5B7, Canada
| | - Yang Song
- Department of Physics and Astronomy, University of Western Ontario, London, ON N6A 3K7, Canada
- Department of Chemistry, University of Western Ontario, London, ON N6A 5B7, Canada
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20
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P SK, Genova A, Pavanello M. Cooperation and Environment Characterize the Low-Lying Optical Spectrum of Liquid Water. J Phys Chem Lett 2017; 8:5077-5083. [PMID: 28968128 DOI: 10.1021/acs.jpclett.7b02212] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The optical spectrum of liquid water is analyzed by subsystem time-dependent density functional theory. We provide simple explanations for several important (and so far elusive) features. Due to the disordered environment surrounding each water molecule, the joint density of states of the liquid is much broader than that of the vapor, thus explaining the red-shifted Urbach tail of the liquid compared to the gas phase. Confinement effects provided by the first solvation shell are responsible for the blue shift of the first absorption peak compared to the vapor. In addition, we also characterize many-body excitonic effects. These dramatically affect the spectral weights at low frequencies, contributing to the refractive index by a small but significant amount.
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Affiliation(s)
- Sudheer Kumar P
- Department of Chemistry, Rutgers University , Newark, New Jersey 07102, United States
| | - Alessandro Genova
- Department of Chemistry, Rutgers University , Newark, New Jersey 07102, United States
| | - Michele Pavanello
- Department of Chemistry, Rutgers University , Newark, New Jersey 07102, United States
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21
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Marin TW, Janik I, Bartels DM, Chipman DM. Vacuum ultraviolet spectroscopy of the lowest-lying electronic state in subcritical and supercritical water. Nat Commun 2017; 8:15435. [PMID: 28513601 PMCID: PMC5442368 DOI: 10.1038/ncomms15435] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Accepted: 03/29/2017] [Indexed: 11/10/2022] Open
Abstract
The nature and extent of hydrogen bonding in water has been scrutinized for decades, including how it manifests in optical properties. Here we report vacuum ultraviolet absorption spectra for the lowest-lying electronic state of subcritical and supercritical water. For subcritical water, the spectrum redshifts considerably with increasing temperature, demonstrating the gradual breakdown of the hydrogen-bond network. Tuning the density at 381 °C gives insight into the extent of hydrogen bonding in supercritical water. The known gas-phase spectrum, including its vibronic structure, is duplicated in the low-density limit. With increasing density, the spectrum blueshifts and the vibronic structure is quenched as the water monomer becomes electronically perturbed. Fits to the supercritical water spectra demonstrate consistency with dimer/trimer fractions calculated from the water virial equation of state and equilibrium constants. Using the known water dimer interaction potential, we estimate the critical distance between molecules (ca. 4.5 Å) needed to explain the vibronic structure quenching. The link between hydrogen bonding and the optical properties of water has been debated for many years, but not fully understood. Here, the authors report vacuum ultraviolet absorption spectra for subcritical and supercritical water, providing insight into the electronic structure of water and its relation to hydrogen bonding.
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Affiliation(s)
- Timothy W Marin
- Department of Chemistry, Benedictine University, 5700 College Road, Lisle, Illinois 60532, USA
| | - Ireneusz Janik
- Notre Dame Radiation Laboratory, Notre Dame, Indiana 46556, USA
| | - David M Bartels
- Notre Dame Radiation Laboratory, Notre Dame, Indiana 46556, USA
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22
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de Wergifosse M, Elles CG, Krylov AI. Two-photon absorption spectroscopy of stilbene and phenanthrene: Excited-state analysis and comparison with ethylene and toluene. J Chem Phys 2017; 146:174102. [DOI: 10.1063/1.4982045] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Marc de Wergifosse
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, USA
| | | | - Anna I. Krylov
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, USA
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23
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Ziaei V, Bredow T. Red and blue shift of liquid water’s excited states: A many body perturbation study. J Chem Phys 2016. [DOI: 10.1063/1.4960561] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Vafa Ziaei
- Mulliken Center for Theoretical Chemistry, University of Bonn, Bonn, Germany
| | - Thomas Bredow
- Mulliken Center for Theoretical Chemistry, University of Bonn, Bonn, Germany
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24
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Houk AL, Givens RS, Elles CG. Two-Photon Activation of p-Hydroxyphenacyl Phototriggers: Toward Spatially Controlled Release of Diethyl Phosphate and ATP. J Phys Chem B 2016; 120:3178-86. [PMID: 26962676 DOI: 10.1021/acs.jpcb.5b12150] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Two-photon activation of the p-hydroxyphenacyl (pHP) photoactivated protecting group is demonstrated for the first time using visible light at 550 nm from a pulsed laser. Broadband two-photon absorption measurements reveal a strong two-photon transition (>10 GM) near 4.5 eV that closely resembles the lowest-energy band at the same total excitation energy in the one-photon absorption spectrum of the pHP chromophore. The polarization dependence of the two-photon absorption band is consistent with excitation to the same S3 ((1)ππ*) excited state for both one- and two-photon activation. Monitoring the progress of the uncaging reaction under nonresonant excitation at 550 nm confirms a quadratic intensity dependence and that two-photon activation of the uncaging reaction is possible using visible light in the range 500-620 nm. Deprotonation of the pHP chromophore under mildly basic conditions shifts the absorption band to lower energy (3.8 eV) in both the one- and two-photon absorption spectra, suggesting that two-photon activation of the pHP chromophore may be possible using light in the range 550-720 nm. The results of these measurements open the possibility of spatially and temporally selective release of biologically active compounds from the pHP protecting group using visible light from a pulsed laser.
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Affiliation(s)
- Amanda L Houk
- Department of Chemistry, University of Kansas , Lawrence, Kansas 66045, United States
| | - Richard S Givens
- Department of Chemistry, University of Kansas , Lawrence, Kansas 66045, United States
| | - Christopher G Elles
- Department of Chemistry, University of Kansas , Lawrence, Kansas 66045, United States
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25
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Nanda KD, Krylov AI. Two-photon absorption cross sections within equation-of-motion coupled-cluster formalism using resolution-of-the-identity and Cholesky decomposition representations: Theory, implementation, and benchmarks. J Chem Phys 2015; 142:064118. [PMID: 25681898 DOI: 10.1063/1.4907715] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The equation-of-motion coupled-cluster (EOM-CC) methods provide a robust description of electronically excited states and their properties. Here, we present a formalism for two-photon absorption (2PA) cross sections for the equation-of-motion for excitation energies CC with single and double substitutions (EOM-CC for electronically excited states with single and double substitutions) wave functions. Rather than the response theory formulation, we employ the expectation-value approach which is commonly used within EOM-CC, configuration interaction, and algebraic diagrammatic construction frameworks. In addition to canonical implementation, we also exploit resolution-of-the-identity (RI) and Cholesky decomposition (CD) for the electron-repulsion integrals to reduce memory requirements and to increase parallel efficiency. The new methods are benchmarked against the CCSD and CC3 response theories for several small molecules. We found that the expectation-value 2PA cross sections are within 5% from the quadratic response CCSD values. The RI and CD approximations lead to small errors relative to the canonical implementation (less than 4%) while affording computational savings. RI/CD successfully address the well-known issue of large basis set requirements for 2PA cross sections calculations. The capabilities of the new code are illustrated by calculations of the 2PA cross sections for model chromophores of the photoactive yellow and green fluorescent proteins.
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Affiliation(s)
- Kaushik D Nanda
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, USA
| | - Anna I Krylov
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, USA
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26
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Houk AL, Zheldakov IL, Tommey TA, Elles CG. Two-Photon Excitation of trans-Stilbene: Spectroscopy and Dynamics of Electronically Excited States above S1. J Phys Chem B 2014; 119:9335-44. [DOI: 10.1021/jp509959n] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Amanda L. Houk
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Igor L. Zheldakov
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Tyler A. Tommey
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
| | - Christopher G. Elles
- Department of Chemistry, University of Kansas, Lawrence, Kansas 66045, United States
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27
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Roberts GM, Marroux HJB, Grubb MP, Ashfold MNR, Orr-Ewing AJ. On the Participation of Photoinduced N–H Bond Fission in Aqueous Adenine at 266 and 220 nm: A Combined Ultrafast Transient Electronic and Vibrational Absorption Spectroscopy Study. J Phys Chem A 2014; 118:11211-25. [DOI: 10.1021/jp508501w] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Gareth M. Roberts
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Hugo J. B. Marroux
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Michael P. Grubb
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Michael N. R. Ashfold
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
| | - Andrew J. Orr-Ewing
- School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, United Kingdom
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28
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Rohmann C, Metson JB, Idriss H. A DFT study on carbon monoxide adsorption onto hydroxylated α-Al₂O₃(0001) surfaces. Phys Chem Chem Phys 2014; 16:14287-97. [PMID: 24915608 DOI: 10.1039/c4cp01373e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The adsorption of CO onto the hydroxylated α-Al2O3(0001) surface was studied using density functional theory (DFT). Dissociated adsorption of water was found to be stable, with an adsorption energy (Ea) of 1.62 eV at θ(water) = 0.75. The most stable hydroxylation form on the clean surface was found to be in the 1-2 dissociation configuration, where the OH group binds to a surface Al ion and the H ion binds to one of the three equivalent surface O ions. The adsorption energy of CO was found to be dependent on the degree of pre-hydroxylation of the surface as well as on the CO coverage. The highest adsorption energy of CO was found when θ(CO) = 0.25 on a pre-hydroxylated surface with θ(water) = 0.25; Ea = 0.57 eV. The adsorption energy of CO decreased upon increasing the degree of pre-hydroxylation. The vibrational frequency of ν(CO) was also computed and in all cases it was blue shifted with respect to gas-phase CO. The shift, Δν, decreased with increasing CO coverage but increased with increasing surface hydroxylation. A comparison with available experimental work is discussed.
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Affiliation(s)
- C Rohmann
- School of Chemical Sciences, The University of Auckland, Auckland, New Zealand
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29
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Grubb MP, Orr-Ewing AJ, Ashfold MNR. KOALA: a program for the processing and decomposition of transient spectra. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:064104. [PMID: 24985828 DOI: 10.1063/1.4884516] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Extracting meaningful kinetic traces from time-resolved absorption spectra is a non-trivial task, particularly for solution phase spectra where solvent interactions can substantially broaden and shift the transition frequencies. Typically, each spectrum is composed of signal from a number of molecular species (e.g., excited states, intermediate complexes, product species) with overlapping spectral features. Additionally, the profiles of these spectral features may evolve in time (i.e., signal nonlinearity), further complicating the decomposition process. Here, we present a new program for decomposing mixed transient spectra into their individual component spectra and extracting the corresponding kinetic traces: KOALA (Kinetics Observed After Light Absorption). The software combines spectral target analysis with brute-force linear least squares fitting, which is computationally efficient because of the small nonlinear parameter space of most spectral features. Within, we demonstrate the application of KOALA to two sets of experimental transient absorption spectra with multiple mixed spectral components. Although designed for decomposing solution-phase transient absorption data, KOALA may in principle be applied to any time-evolving spectra with multiple components.
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Affiliation(s)
- Michael P Grubb
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Andrew J Orr-Ewing
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Michael N R Ashfold
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
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30
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Chen J, Zhang Y, Kohler B. Excited States in DNA Strands Investigated by Ultrafast Laser Spectroscopy. PHOTOINDUCED PHENOMENA IN NUCLEIC ACIDS II 2014; 356:39-87. [DOI: 10.1007/128_2014_570] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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31
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Urbanek J, Vöhringer P. Below-Band-Gap Ionization of Liquid-to-Supercritical Ammonia: Geminate Recombination via Proton-Coupled Back Electron Transfer. J Phys Chem B 2013; 118:265-77. [DOI: 10.1021/jp4103993] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Janus Urbanek
- Abteilung für Molekulare
Physikalische Chemie, Institut für Physikalische und Theoretische
Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße 12, 53115 Bonn, Germany
| | - Peter Vöhringer
- Abteilung für Molekulare
Physikalische Chemie, Institut für Physikalische und Theoretische
Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße 12, 53115 Bonn, Germany
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32
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Zhang Y, Oliver TAA, Das S, Roy A, Ashfold MNR, Bradforth SE. Exploring the Energy Disposal Immediately After Bond-Breaking in Solution: The Wavelength-Dependent Excited State Dissociation Pathways of para-Methylthiophenol. J Phys Chem A 2013; 117:12125-37. [DOI: 10.1021/jp405160n] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yuyuan Zhang
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | - Thomas A. A. Oliver
- School of Chemistry, Cantocks Close, University of Bristol, Bristol BS8 1TS, U.K
| | - Saptaparna Das
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | - Anirban Roy
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
| | | | - Stephen E. Bradforth
- Department
of Chemistry, University of Southern California, Los Angeles, California 90089-0482, United States
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33
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Landau A. Similarity transformed coupled cluster response (ST-CCR) theory - A time-dependent similarity transformed equation-of-motion coupled cluster (STEOM-CC) approach. J Chem Phys 2013; 139:014110. [DOI: 10.1063/1.4811799] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Zhang Y, Oliver TAA, Ashfold MNR, Bradforth SE. Contrasting the excited state reaction pathways of phenol and para-methylthiophenol in the gas and liquid phases. Faraday Discuss 2013; 157:141-63; discussion 243-84. [PMID: 23230767 DOI: 10.1039/c2fd20043k] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To explore how the solvent influences primary aspects of bond breaking, the gas and solution phase photochemistries of phenol and ofpara-methylthiophenol are directly compared using, respectively, H (Rydberg) atom photofragment translation spectroscopy and femtosecond transient absorption spectroscopy. Approaches are demonstrated that allow explicit comparisons of the nascent product energy disposals and dissociation mechanisms in the two phases. It is found, at least for the case of the weakly perturbing cyclohexane environment, that most aspects of the primary reaction dynamics of the isolated molecule are reproduced in solution. Specifically, in the gas phase, both molecules can undergo fast X-H (X = O, S) bond dissociation upon excitation with short wavelengths (193 < lambda(pump) < 216 nm), following population of the dissociative S2 (1 1(pi sigma*)) state. Product electronic branching, vibrational and translational energy disposals are determined. Photolysis of phenol and para-methylthiophenol in solution at 200 nm results in formation of vibrationally excited radicals on a timescale shorter than 200 fs. Excitation of para-methylthiophenol at 267 nm reaches close to the S1 (1 1(pipi*))/S2 (11(pi sigma*)) conical intersection (CI): ultrafast dissociation is observed in both the isolated and solution systems-again indicating direct dissociation on the S2 potential energy surface. Comparing results for this precursor at different excitation energies, the extent of geminate recombination and the derived H-atom ejection lengths in the condensed phase photolyses are in qualitative agreement with the translational energy release measured in the gas phase studies. Conversely, excitation of phenol at 267 nm prepares the system in its S1 state at an energy well below its S1/S2 CI; the slow O-H bond fission inferred in the gas phase experiments is observed directly in the time-resolved studies in cyclohexane solution via the appearance of phenoxyl radical absorption after -1 ns, with only S1 excited state absorption discernible at earlier delay times. The slow O-H bond fission in solution provides additional evidence for a tunnelling dissociation mechanism, where the H atom tunnels beneath the lower diabats of the S2/S1 CI. Finally, the photodissociation of phenol clusters in solution is considered, where evidence is presented that the O-H dissociation coordinate is impeded in H-bonded dimers.
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Affiliation(s)
- Yuyuan Zhang
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089, USA
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35
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Cabral do Couto P, Chipman DM. Insights into the ultraviolet spectrum of liquid water from model calculations: the different roles of donor and acceptor hydrogen bonds in water pentamers. J Chem Phys 2013; 137:184301. [PMID: 23163365 DOI: 10.1063/1.4764044] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
With a view toward a better understanding of changes in the peak position and shape of the first absorption band of water with condensation or temperature, results from electronic structure calculations using high level wavefunction based and time-dependent density functional methods are reported for water pentamers. Excitation energies, oscillator strengths, and redistributions of electron density are determined for the quasitetrahedral water pentamer in its C(2v) equilibrium geometry and for many pentamer configurations sampled from molecular simulation of liquid water. Excitations associated with surface molecules are removed in order to focus on those states associated with the central molecule, which are the most representative of the liquid environment. The effect of hydrogen bonding on the lowest excited state associated with the central molecule is studied by adding acceptor or donor hydrogen bonds to tetramer and trimer substructures of the C(2v) pentamer, and by sampling liquid-like configurations having increasing number of acceptor or donor hydrogen bonds of the central molecule. Our results provide clear evidence that the blueshift of excitation energies upon condensation is essentially determined by acceptor hydrogen bonds, and the magnitudes of these shifts are determined by the number of such, whereas donor hydrogen bonds do not induce significant shifts in excitation energies. This qualitatively different role of donor and acceptor hydrogen bonds is understood in terms of the different roles of the 1b(1) monomer molecular orbitals, which establishes an intimate connection between the valence hole and excitation energy shifts. Since the valence hole of the lowest excitation associated with the central molecule is found to be well localized in all liquid-like hydrogen bonding environments, with an average radius of gyration of ~1.6 Å that is much lower than the nearest neighbor O-O distance, a clear and unambiguous connection between hydrogen bonding environments and excitation energy shifts can be established. Based on these results, it is concluded that peak position of the first absorption band is mainly determined by the relative distribution of single and double acceptor hydrogen bonding environments, whereas the shape of the first absorption band is mainly determined by the relative distribution of acceptor and broken acceptor hydrogen bonding environments. The temperature dependence of the peak position and shape of the first absorption band can be readily understood in terms of changes to these relative populations.
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Affiliation(s)
- Paulo Cabral do Couto
- Notre Dame Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, USA
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Marsalek O, Elles CG, Pieniazek PA, Pluhařová E, VandeVondele J, Bradforth SE, Jungwirth P. Chasing charge localization and chemical reactivity following photoionization in liquid water. J Chem Phys 2012; 135:224510. [PMID: 22168706 DOI: 10.1063/1.3664746] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The ultrafast dynamics of the cationic hole formed in bulk liquid water following ionization is investigated by ab initio molecular dynamics simulations and an experimentally accessible signature is suggested that might be tracked by femtosecond pump-probe spectroscopy. This is one of the fastest fundamental processes occurring in radiation-induced chemistry in aqueous systems and biological tissue. However, unlike the excess electron formed in the same process, the nature and time evolution of the cationic hole has been hitherto little studied. Simulations show that an initially partially delocalized cationic hole localizes within ~30 fs after which proton transfer to a neighboring water molecule proceeds practically immediately, leading to the formation of the OH radical and the hydronium cation in a reaction which can be formally written as H(2)O(+) + H(2)O → OH + H(3)O(+). The exact amount of initial spin delocalization is, however, somewhat method dependent, being realistically described by approximate density functional theory methods corrected for the self-interaction error. Localization, and then the evolving separation of spin and charge, changes the electronic structure of the radical center. This is manifested in the spectrum of electronic excitations which is calculated for the ensemble of ab initio molecular dynamics trajectories using a quantum mechanics/molecular mechanics (QM∕MM) formalism applying the equation of motion coupled-clusters method to the radical core. A clear spectroscopic signature is predicted by the theoretical model: as the hole transforms into a hydroxyl radical, a transient electronic absorption in the visible shifts to the blue, growing toward the near ultraviolet. Experimental evidence for this primary radiation-induced process is sought using femtosecond photoionization of liquid water excited with two photons at 11 eV. Transient absorption measurements carried out with ~40 fs time resolution and broadband spectral probing across the near-UV and visible are presented and direct comparisons with the theoretical simulations are made. Within the sensitivity and time resolution of the current measurement, a matching spectral signature is not detected. This result is used to place an upper limit on the absorption strength and/or lifetime of the localized H(2)O(+) ((aq)) species.
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Affiliation(s)
- Ondrej Marsalek
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic and Center for Biomolecules and Complex Molecular Systems, Flemingovo nám. 2, 16610 Prague 6, Czech Republic
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37
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Urbanek J, Dahmen A, Torres-Alacan J, Königshoven P, Lindner J, Vöhringer P. Femtosecond Two-Photon Ionization and Solvated Electron Geminate Recombination in Liquid-to-Supercritical Ammonia. J Phys Chem B 2012; 116:2223-33. [DOI: 10.1021/jp211725r] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Janus Urbanek
- Abteilung
für Molekulare Physikalische Chemie,
Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße
12, 53115 Bonn, Germany
| | - Annika Dahmen
- Abteilung
für Molekulare Physikalische Chemie,
Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße
12, 53115 Bonn, Germany
| | - Joel Torres-Alacan
- Abteilung
für Molekulare Physikalische Chemie,
Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße
12, 53115 Bonn, Germany
| | - Peter Königshoven
- Abteilung
für Molekulare Physikalische Chemie,
Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße
12, 53115 Bonn, Germany
| | - Jörg Lindner
- Abteilung
für Molekulare Physikalische Chemie,
Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße
12, 53115 Bonn, Germany
| | - Peter Vöhringer
- Abteilung
für Molekulare Physikalische Chemie,
Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms-Universität, Wegelerstraße
12, 53115 Bonn, Germany
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38
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Rivera CA, Winter N, Harper RV, Benjamin I, Bradforth SE. The dynamical role of solvent on the ICN photodissociation reaction: connecting experimental observables directly with molecular dynamics simulations. Phys Chem Chem Phys 2011; 13:8269-83. [DOI: 10.1039/c1cp20252a] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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39
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Oliver TAA, Zhang Y, Ashfold MNR, Bradforth SE. Linking photochemistry in the gas and solution phase: S–H bond fission in p-methylthiophenol following UV photoexcitation. Faraday Discuss 2011; 150:439-58; discussion 505-32. [DOI: 10.1039/c0fd00031k] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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40
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Livshits E, Granot RS, Baer R. A Density Functional Theory for Studying Ionization Processes in Water Clusters. J Phys Chem A 2010; 115:5735-44. [DOI: 10.1021/jp1057572] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Ester Livshits
- Fritz Haber Center for Molecular Dynamics, Chaim Weizmann Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Rebecca S. Granot
- Fritz Haber Center for Molecular Dynamics, Chaim Weizmann Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Roi Baer
- Fritz Haber Center for Molecular Dynamics, Chaim Weizmann Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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41
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Cabral do Couto P, Chipman DM. Insights into the ultraviolet spectrum of liquid water from model calculations. J Chem Phys 2010; 132:244307. [PMID: 20590193 DOI: 10.1063/1.3453248] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
With a view toward a better molecular level understanding of the effects of hydrogen bonding on the ultraviolet absorption spectrum of liquid water, benchmark electronic structure calculations using high level wave function based methods and systematically enlarged basis sets are reported for excitation energies and oscillator strengths of valence excited states in the equilibrium water monomer and dimer and in a selection of liquid-like dimer structures. Analysis of the electron density redistribution associated with the two lowest valence excitations of the water dimer shows that these are usually localized on one or the other monomer, although valence hole delocalization can occur for certain relative orientations of the water molecules. The lowest excited state is mostly associated with the hydrogen bond donor and the significantly higher energy second excited state mostly with the acceptor. The magnitude of the lowest excitation energies is strongly dependent on where the valence hole is created, and only to a lesser degree on the perturbation of the excited electron density distribution by the neighboring water molecule. These results suggest that the lowest excitation energies in clusters and liquid water can be associated with broken acceptor hydrogen bonds, which provide energetically favorable locations for the formation of a valence hole. Higher valence excited states of the dimer typically involve delocalization of the valence hole and/or delocalization of the excited electron and/or charge transfer. Two of the higher valence excited states that involve delocalized valence holes always have particularly large oscillator strengths. Due to the pervasive delocalization and charge transfer, it is suggested that most condensed phase water valence excitations intimately involve more than one water molecule and, as a consequence, will not be adequately described by models based on perturbation of free water monomer states. The benchmark calculations are further used to evaluate a series of representative semilocal, global hybrid, and range separated hybrid functionals used in efficient time-dependent density functional methods. It is shown that such an evaluation is only meaningful when comparison is made at or near the complete basis set limit of the wave function based reference method. A functional is found that quantitatively describes the two lowest excitations of water dimer and also provides a semiquantitative description of the higher energy valence excited states. This functional is recommended for use in further studies on the absorption spectrum of large water clusters and of condensed phase water.
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Kratz S, Torres-Alacan J, Urbanek J, Lindner J, Vöhringer P. Geminate recombination of hydrated electrons in liquid-to-supercritical water studied by ultrafast time-resolved spectroscopy. Phys Chem Chem Phys 2010; 12:12169-76. [DOI: 10.1039/c0cp00762e] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Pieniazek PA, Lin YS, Chowdhary J, Ladanyi BM, Skinner JL. Vibrational Spectroscopy and Dynamics of Water Confined inside Reverse Micelles. J Phys Chem B 2009; 113:15017-28. [DOI: 10.1021/jp906784t] [Citation(s) in RCA: 126] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Piotr A. Pieniazek
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, and Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | - Yu-Shan Lin
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, and Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | - Janamejaya Chowdhary
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, and Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | - Branka M. Ladanyi
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, and Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
| | - J. L. Skinner
- Theoretical Chemistry Institute and Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, and Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523
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44
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Chipman DM. Vertical electronic excitation with a dielectric continuum model of solvation including volume polarization. II. Implementation and applications. J Chem Phys 2009; 131:014104. [DOI: 10.1063/1.3157465] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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45
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Brown MA, Faubel M, Winter B. X-Ray photo- and resonant Auger-electron spectroscopy studies of liquid water and aqueous solutions. ACTA ACUST UNITED AC 2009. [DOI: 10.1039/b803023p] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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