1
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Kamimura R, Maeda S, Hayashi T, Motobayashi K, Ikeda K. Why Is Surface-Enhanced Raman Scattering Insensitive to Liquid Water? J Am Chem Soc 2024; 146:22327-22334. [PMID: 39102527 DOI: 10.1021/jacs.4c04901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/07/2024]
Abstract
Surface-enhanced Raman scattering (SERS) is widely recognized as a remarkably powerful analytical technique that enables trace-level detection of organic molecules on a metal surface in aqueous systems with negligible spectral interference of water. This insensitivity of SERS to liquid water is violated in a restrictive manner under specific electrochemical conditions. However, the origin of such different SERS sensitivities to liquid water remains unclear. Here, we show that hydrogen-bond networks of water play a pivotal role in losing SERS enhancement for liquid water, and SERS detection of water requires local defects in the hydrogen-bond networks, which are formed around hydration shells of solute ions or on a polarized electrode surface. This work gives a new perspective on in situ SERS investigations in aqueous systems, including electrochemical and biological reactions.
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Affiliation(s)
- Ryuto Kamimura
- Program of Applied Physics, Department of Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
| | - Shoichi Maeda
- Department of Materials Science and Engineering, School of Materials Science and Chemical Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8502, Japan
| | - Tomohiro Hayashi
- Department of Materials Science and Engineering, School of Materials Science and Chemical Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8502, Japan
| | - Kenta Motobayashi
- Program of Applied Physics, Department of Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
| | - Katsuyoshi Ikeda
- Program of Applied Physics, Department of Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
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2
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Lu H, Macht M, Rosenberg R, Wiedenbeck E, Lukas M, Qi D, Maltseva D, Zahn D, Cölfen H, Bonn M. Organic Nucleation: Water Rearrangement Reveals the Pathway of Ibuprofen. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2307858. [PMID: 38269485 DOI: 10.1002/smll.202307858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 12/31/2023] [Indexed: 01/26/2024]
Abstract
The organic nucleation of the pharmaceutical ibuprofen is investigated, as triggered by the protonation of ibuprofen sodium salt at elevated pH. The growth and aggregation of nanoscale solution species by Analytical Ultracentrifugation and Molecular Dynamics (MD) simulations is tracked. Both approaches reveal solvated molecules, oligomers, and prenucleation clusters, their size as well as their hydration at different reaction stages. By combining surface-specific vibrational spectroscopy and MD simulations, water interacting with ibuprofen at the air-water interface during nucleation is probed. The results show the structure of water changes upon ibuprofen protonation in response to the charge neutralization. Remarkably, the water structure continues to evolve despite the saturation of protonated ibuprofen at the hydrophobic interface. This further water rearrangement is associated with the formation of larger aggregates of ibuprofen molecules at a late prenucleation stage. The nucleation of ibuprofen involves ibuprofen protonation and their hydrophobic assembly. The results highlight that these processes are accompanied by substantial water reorganization. The critical role of water is possibly relevant for organic nucleation in aqueous environments in general.
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Affiliation(s)
- Hao Lu
- Department of Materials and Textile Engineering, Nanotechnology Research Institute, Jiaxing University, Jiaxing, Zhejiang Province, 314001, P. R. China
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Moritz Macht
- Lehrstuhl für Theoretische Chemie/Computer Chemie Centrum, Friedrich-Alexander Universität Erlangen-Nürnberg, Nägelsbachstraße 25, 91052, Erlangen, Germany
| | - Rose Rosenberg
- Physical Chemistry, Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Eduard Wiedenbeck
- Physical Chemistry, Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Max Lukas
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Daizong Qi
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Daria Maltseva
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Dirk Zahn
- Lehrstuhl für Theoretische Chemie/Computer Chemie Centrum, Friedrich-Alexander Universität Erlangen-Nürnberg, Nägelsbachstraße 25, 91052, Erlangen, Germany
| | - Helmut Cölfen
- Physical Chemistry, Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
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3
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Cho YC, Lee S, Wang L, Lee YH, Kim S, Lee HH, Lee JJ, Lee GW. Impact of molecular symmetry on crystallization pathways in highly supersaturated KH 2PO 4 solutions. Nat Commun 2024; 15:3117. [PMID: 38600081 PMCID: PMC11006877 DOI: 10.1038/s41467-024-47503-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 04/01/2024] [Indexed: 04/12/2024] Open
Abstract
Solute structure and its evolution in supersaturated aqueous solutions are key clues to understand Ostwald's step rule. Here, we measure the structural evolution of solute molecules in highly supersaturated solutions of KH2PO4 (KDP) and NH4H2PO4 (ADP) using a combination of electrostatic levitation and synchrotron X-ray scattering. The measurement reveals the existence of a solution-solution transition in KDP solution, caused by changing molecular symmetries and structural evolution of the solution with supersaturation. Moreover, we find that the molecular symmetry of H2PO4- impacts on phase selection. These findings manifest that molecular symmetry and its structural evolution can govern the crystallization pathways in aqueous solutions, explaining the microscopic origin of Ostwald's step rule.
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Affiliation(s)
- Yong Chan Cho
- Frontier of Extreme Physics, Korea Research Institute of Standards and Science, Daejeon, 34113, Republic of Korea
| | - Sooheyong Lee
- Frontier of Extreme Physics, Korea Research Institute of Standards and Science, Daejeon, 34113, Republic of Korea
- Applied Measurement Science, University of Science and Technology, Daejeon, 34113, Republic of Korea
| | - Lei Wang
- Frontier of Extreme Physics, Korea Research Institute of Standards and Science, Daejeon, 34113, Republic of Korea
| | - Yun-Hee Lee
- Frontier of Extreme Physics, Korea Research Institute of Standards and Science, Daejeon, 34113, Republic of Korea
| | - Seongheun Kim
- Pohang Accelerator Laboratory, POSTECH, Pohang, 37673, Republic of Korea
| | - Hyun-Hwi Lee
- Pohang Accelerator Laboratory, POSTECH, Pohang, 37673, Republic of Korea
| | - John Jonghyun Lee
- Department of Mechanical Engineering, Iowa State University, Ames, IA, 50011, USA
| | - Geun Woo Lee
- Frontier of Extreme Physics, Korea Research Institute of Standards and Science, Daejeon, 34113, Republic of Korea.
- Applied Measurement Science, University of Science and Technology, Daejeon, 34113, Republic of Korea.
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4
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Finney AR, Salvalaglio M. Properties of aqueous electrolyte solutions at carbon electrodes: effects of concentration and surface charge on solution structure, ion clustering and thermodynamics in the electric double layer. Faraday Discuss 2024; 249:334-362. [PMID: 37781909 DOI: 10.1039/d3fd00133d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
Surfaces are able to control physical-chemical processes in multi-component solution systems and, as such, find application in a wide range of technological devices. Understanding the structure, dynamics and thermodynamics of non-ideal solutions at surfaces, however, is particularly challenging. Here, we use Constant Chemical Potential Molecular Dynamics (CμMD) simulations to gain insight into aqueous NaCl solutions in contact with graphite surfaces at high concentrations and under the effect of applied surface charges: conditions where mean-field theories describing interfaces cannot (typically) be reliably applied. We discover an asymmetric effect of surface charge on the electric double layer structure and resulting thermodynamic properties, which can be explained by considering the affinity of the surface for cations and anions and the cooperative adsorption of ions that occurs at higher concentrations. We characterise how the sign of the surface charge affects ion densities and water structure in the double layer and how the capacitance of the interface-a function of the electric potential drop across the double layer-is largely insensitive to the bulk solution concentration. Notably, we find that negatively charged graphite surfaces induce an increase in the size and concentration of extended liquid-like ion clusters confined to the double layer. Finally, we discuss how concentration and surface charge affect the activity coefficients of ions and water at the interface, demonstrating how electric fields in this region should be explicitly considered when characterising the thermodynamics of both solute and solvent at the solid/liquid interface.
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Affiliation(s)
- Aaron R Finney
- Thomas Young Centre and Department of Chemical Engineering, University College London, London WC1E 7JE, UK.
| | - Matteo Salvalaglio
- Thomas Young Centre and Department of Chemical Engineering, University College London, London WC1E 7JE, UK.
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5
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Wang R, Mehdi S, Zou Z, Tiwary P. Is the Local Ion Density Sufficient to Drive NaCl Nucleation from the Melt and Aqueous Solution? J Phys Chem B 2024; 128:1012-1021. [PMID: 38262436 DOI: 10.1021/acs.jpcb.3c06735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Even though nucleation is ubiquitous in different science and engineering problems, investigating nucleation is extremely difficult due to the complicated ranges of time and length scales involved. In this work, we simulate NaCl nucleation in both molten and aqueous environments using enhanced sampling of all-atom molecular dynamics with deep-learning-based estimation of reaction coordinates. By incorporating various structural order parameters and learning the reaction coordinate as a function thereof, we achieve significantly improved sampling relative to traditional ad hoc descriptions of what drives nucleation, particularly in an aqueous medium. Our results reveal a one-step nucleation mechanism in both environments, with reaction coordinate analysis highlighting the importance of local ion density in distinguishing solid and liquid states. However, although fluctuations in the local ion density are necessary to drive nucleation, they are not sufficient. Our analysis shows that near the transition states, descriptors such as enthalpy and local structure become crucial. Our protocol proposed here enables robust nucleation analysis and phase sampling and could offer insights into nucleation mechanisms for generic small molecules in different environments.
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Affiliation(s)
- Ruiyu Wang
- Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, United States
| | - Shams Mehdi
- Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, United States
- Biophysics Program, University of Maryland, College Park, Maryland 20742, United States
| | - Ziyue Zou
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
| | - Pratyush Tiwary
- Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, United States
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, United States
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6
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Kim M, Kim YJ, Cho YC, Lee S, Kim S, Liermann HP, Lee YH, Lee GW. Simultaneous measurements of volume, pressure, optical images, and crystal structure with a dynamic diamond anvil cell: A real-time event monitoring system. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:113904. [PMID: 38015123 DOI: 10.1063/5.0166090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 10/31/2023] [Indexed: 11/29/2023]
Abstract
The dynamic diamond anvil cell (dDAC) technique has attracted great interest because it possibly provides a bridge between static and dynamic compression studies with fast, repeatable, and controllable compression rates. The dDAC can be a particularly useful tool to study the pathways and kinetics of phase transitions under dynamic pressurization if simultaneous measurements of physical quantities are possible as a function of time. We here report the development of a real-time event monitoring (RTEM) system with dDAC, which can simultaneously record the volume, pressure, optical image, and structure of materials during dynamic compression runs. In particular, the volume measurement using both Fabry-Pérot interferogram and optical images facilitates the construction of an equation of state (EoS) using the dDAC in a home-laboratory. We also developed an in-line ruby pressure measurement (IRPM) system to be deployed at a synchrotron x-ray facility. This system provides simultaneous measurements of pressure and x-ray diffraction in low and narrow pressure ranges. The EoSs of ice VI obtained from the RTEM and the x-ray diffraction data with the IRPM are consistent with each other. The complementarity of both RTEM and IRPM systems will provide a great opportunity to scrutinize the detailed kinetic pathways of phase transitions using dDAC.
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Affiliation(s)
- Minju Kim
- Frontier of Extreme Physics, Interdisciplinary Materials Measurement Institute, Korea Research Institute of Standards and Science, Daejeon 34113, Republic of Korea
| | - Yong-Jae Kim
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Yong Chan Cho
- Frontier of Extreme Physics, Interdisciplinary Materials Measurement Institute, Korea Research Institute of Standards and Science, Daejeon 34113, Republic of Korea
| | - Sooheyong Lee
- Frontier of Extreme Physics, Interdisciplinary Materials Measurement Institute, Korea Research Institute of Standards and Science, Daejeon 34113, Republic of Korea
- Applied Measurement Science, University of Science and Technology, Daejeon, Daejeon 34113, Republic of Korea
| | - Seongheun Kim
- Pohang Accelerator Laboratory, POSTECH, Pohang 37673, Republic of Korea
| | | | - Yun-Hee Lee
- Frontier of Extreme Physics, Interdisciplinary Materials Measurement Institute, Korea Research Institute of Standards and Science, Daejeon 34113, Republic of Korea
| | - Geun Woo Lee
- Frontier of Extreme Physics, Interdisciplinary Materials Measurement Institute, Korea Research Institute of Standards and Science, Daejeon 34113, Republic of Korea
- Applied Measurement Science, University of Science and Technology, Daejeon, Daejeon 34113, Republic of Korea
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7
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Cedeno R, Grossier R, Candoni N, Levernier N, Flood AE, Veesler S. CNT effective interfacial energy and pre-exponential kinetic factor from measured NaCl crystal nucleation time distributions in contracting microdroplets. J Chem Phys 2023; 158:2891367. [PMID: 37191406 DOI: 10.1063/5.0143704] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 03/29/2023] [Indexed: 05/17/2023] Open
Abstract
Nucleation, the birth of a stable cluster from a disorder, is inherently stochastic. Yet up to date, there are no quantitative studies on NaCl nucleation that accounts for its stochastic nature. Here, we report the first stochastic treatment of NaCl-water nucleation kinetics. Using a recently developed microfluidic system and evaporation model, our measured interfacial energies extracted from a modified Poisson distribution of nucleation time show an excellent agreement with theoretical predictions. Furthermore, analysis of nucleation parameters in 0.5, 1.5, and 5.5 pl microdroplets reveals an interesting interplay between confinement effects and shifting of nucleation mechanisms. Overall, our findings highlight the need to treat nucleation stochastically rather than deterministically to bridge the gap between theory and experiment.
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Affiliation(s)
- Ruel Cedeno
- CNRS, Aix-Marseille University, CINaM (Centre Interdisciplinaire de Nanosciences de Marseille), Campus de Luminy, Case 913, F-13288 Marseille Cedex 09, France
- Department of Chemical and Biomolecular Engineering, School of Energy Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Rayong 21210, Thailand
| | - Romain Grossier
- CNRS, Aix-Marseille University, CINaM (Centre Interdisciplinaire de Nanosciences de Marseille), Campus de Luminy, Case 913, F-13288 Marseille Cedex 09, France
| | - Nadine Candoni
- CNRS, Aix-Marseille University, CINaM (Centre Interdisciplinaire de Nanosciences de Marseille), Campus de Luminy, Case 913, F-13288 Marseille Cedex 09, France
| | - Nicolas Levernier
- INMED, INSERM, Aix Marseille University, Turing Centre for Living Systems, Marseille, France
- Aix-Marseille University, Université de Toulon, CNRS, CPT (UMR 7332), Turing Centre for Living Systems, Marseille, France
| | - Adrian E Flood
- Department of Chemical and Biomolecular Engineering, School of Energy Science and Engineering, Vidyasirimedhi Institute of Science and Technology, Rayong 21210, Thailand
| | - Stéphane Veesler
- CNRS, Aix-Marseille University, CINaM (Centre Interdisciplinaire de Nanosciences de Marseille), Campus de Luminy, Case 913, F-13288 Marseille Cedex 09, France
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8
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Di Pasquale N, Finney AR, Elliott JD, Carbone P, Salvalaglio M. Constant chemical potential-quantum mechanical-molecular dynamics simulations of the graphene-electrolyte double layer. J Chem Phys 2023; 158:134714. [PMID: 37031135 DOI: 10.1063/5.0138267] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2023] Open
Abstract
We present the coupling of two frameworks-the pseudo-open boundary simulation method known as constant potential molecular dynamics simulations (CμMD), combined with quantum mechanics/molecular dynamics (QMMD) calculations-to describe the properties of graphene electrodes in contact with electrolytes. The resulting CμQMMD model was then applied to three ionic solutions (LiCl, NaCl, and KCl in water) at bulk solution concentrations ranging from 0.5 M to 6 M in contact with a charged graphene electrode. The new approach we are describing here provides a simulation protocol to control the concentration of electrolyte solutions while including the effects of a fully polarizable electrode surface. Thanks to this coupling, we are able to accurately model both the electrode and solution side of the double layer and provide a thorough analysis of the properties of electrolytes at charged interfaces, such as the screening ability of the electrolyte and the electrostatic potential profile. We also report the calculation of the integral electrochemical double layer capacitance in the whole range of concentrations analyzed for each ionic species, while the quantum mechanical simulations provide access to the differential and integral quantum capacitance. We highlight how subtle features, such as the adsorption of potassium graphene or the tendency of the ions to form clusters contribute to the ability of graphene to store charge, and suggest implications for desalination.
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Affiliation(s)
- Nicodemo Di Pasquale
- Department of Chemical Engineering, Brunel University London, Uxbridge UB8 3PH, United Kingdom
| | - Aaron R Finney
- Department of Chemical Engineering, University College London, London WC1E 7JE, United Kingdom
| | - Joshua D Elliott
- Department of Chemical Engineering, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Paola Carbone
- Department of Chemical Engineering, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Matteo Salvalaglio
- Department of Chemical Engineering, University College London, London WC1E 7JE, United Kingdom
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9
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Guo M, Jones MJ, Goh R, Verma V, Guinn E, Heng JYY. The Effect of Chain Length and Conformation on the Nucleation of Glycine Homopeptides during the Crystallization Process. CRYSTAL GROWTH & DESIGN 2023; 23:1668-1675. [PMID: 36879769 PMCID: PMC9983003 DOI: 10.1021/acs.cgd.2c01229] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 01/09/2023] [Indexed: 05/14/2023]
Abstract
To explore the effect of chain length and conformation on the nucleation of peptides, the primary nucleation induction time of glycine homopeptides in pure water at different supersaturation levels under various temperatures has been determined. Nucleation data suggest that longer chains will prolong the induction time, especially for chains longer than three, where nucleation will occur over several days. In contrast, the nucleation rate increased with an increase in the supersaturation for all homopeptides. Induction time and nucleation difficulty increase at lower temperatures. However, for triglycine, the dihydrate form was produced with an unfolded peptide conformation (pPII) at low temperature. The interfacial energy and activation Gibbs energy of this dihydrate form are both lower than those at high temperature, while the induction time is longer, indicating the classical nucleation theory is not suitable to explain the nucleation phenomenon of triglycine dihydrate. Moreover, gelation and liquid-liquid separation of longer chain glycine homopeptides were observed, which was normally classified to nonclassical nucleation theory. This work provides insight into how the nucleation process evolves with increasing chain length and variable conformation, thereby offering a fundamental understanding of the critical peptide chain length for the classical nucleation theory and complex nucleation process for peptides.
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Affiliation(s)
- Mingxia Guo
- Department
of Chemical Engineering, Imperial
College London, South Kensington
Campus, LondonSW7 2AZ, U.K.
| | - Marie J. Jones
- Department
of Chemical Engineering, Imperial
College London, South Kensington
Campus, LondonSW7 2AZ, U.K.
| | - Racheal Goh
- Department
of Chemical Engineering, Imperial
College London, South Kensington
Campus, LondonSW7 2AZ, U.K.
| | - Vivek Verma
- Department
of Chemical Engineering, Imperial
College London, South Kensington
Campus, LondonSW7 2AZ, U.K.
| | - Emily Guinn
- Synthetic
Molecule Design and Development, Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana46221, United States
| | - Jerry Y. Y. Heng
- Department
of Chemical Engineering, Imperial
College London, South Kensington
Campus, LondonSW7 2AZ, U.K.
- Institute
for Molecular Science and Engineering, Imperial
College London, South Kensington
Campus, LondonSW7 2AZ, U.K.
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10
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Huang Y, Wang J, Wang N, Li X, Ji X, Yang J, Zhou L, Wang T, Huang X, Hao H. Molecular mechanism of liquid–liquid phase separation in preparation process of crystalline materials. Chem Eng Sci 2022. [DOI: 10.1016/j.ces.2022.118005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11
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Villa AM, Doglia SM, De Gioia L, Natalello A, Bertini L. Fluorescence of KCl Aqueous Solution: A Possible Spectroscopic Signature of Nucleation. J Phys Chem B 2022; 126:2564-2572. [PMID: 35344657 PMCID: PMC8996234 DOI: 10.1021/acs.jpcb.2c01496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
![]()
Ion pairing
in water solutions alters both the water hydrogen-bond network and
ion solvation, modifying the dynamics and properties of electrolyte
water solutions. Here, we report an anomalous intrinsic fluorescence
of KCl aqueous solution at room temperature and show that its intensity
increases with the salt concentration. From the ab initio density
functional theory (DFT) and time-dependent DFT modeling, we propose
that the fluorescence emission could originate from the stiffening
of the hydrogen bond network in the hydration shell of solvated ion-pairs
that suppresses the fast nonradiative decay and allows the slower
radiative channel to become a possible decay pathway. Because computations
suggest that the fluorophores are the local ion-water structures present
in the prenucleation phase, this band could be the signature of the
incoming salt precipitation.
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Affiliation(s)
- Anna Maria Villa
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy
| | - Silvia Maria Doglia
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy
| | - Luca De Gioia
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy
| | - Antonino Natalello
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy
| | - Luca Bertini
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy
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12
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Lauer A, Duran-Olivencia MA, Fernandez-Martinez A, Van Driessche A. Nucleation precursors compatible with a single energy barrier: catching the nonclassical culprit. Faraday Discuss 2022; 235:95-108. [DOI: 10.1039/d1fd00092f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work we link experimental results of SrSO4 precipitation with a mesoscopic nucleation model (MeNT) to stride towards a cohesive view of the nucleation process integrating both classical and...
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13
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Nonclassical Nucleation—Role of Metastable Intermediate Phase in Crystal Nucleation: An Editorial Prefix. CRYSTALS 2021. [DOI: 10.3390/cryst11020174] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Classical nucleation theory (CNT), which was established about 90 years ago, represents the most commonly used theory in describing nucleation processes. For a fluid-to-solid phase transition, CNT states that the solutes in a supersaturated solution reversibly form small clusters. Once a cluster reaches its critical size, it becomes thermodynamically stable and is favored for further growth. One of the most important assumptions of CNT is that the nucleation process is described by one reaction coordinate and all order parameters proceed simultaneously. Recent studies in experiments, computer simulations, and theory have revealed nonclassical features in the early stage of nucleation. In particular, the decoupling of order parameters involved during a fluid-to-solid transition leads to the so-called two-step nucleation mechanism, in which a metastable intermediate phase (MIP) exists in parallel to the initial supersaturated solution and the final crystals. These MIPs can be high-density liquid phases, mesoscopic clusters, or preordered states. In this Special Issue, we focus on the role of the various MIPs in the early stage of crystal nucleation of organic materials, metals and alloys, aqueous solutions, minerals, colloids, and proteins, and thus on various scenarios of nonclassical pathways of crystallization.
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14
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Finney A, Salvalaglio M. Multiple Pathways in NaCl Homogeneous Crystal Nucleation. Faraday Discuss 2021; 235:56-80. [DOI: 10.1039/d1fd00089f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
NaCl crystal nucleation from metastable solutions has long been considered to occur according to a single-step mechanism where the growth in the size and crystalline order of the emerging nuclei...
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