Article
Multidisciplinary Sciences
Angelo Montenegro, Chayan Dutta, Muhammet Mammetkuliev, Haotian Shi, Bingya Hou, Dhritiman Bhattacharyya, Bofan Zhao, Stephen B. Cronin, Alexander V. Benderskii
Summary: This experimental study reveals that the dielectric response of interfacial water may deviate from linear response, challenging the traditional view of treating interfacial water as a simple dielectric medium. Vibrational sum-frequency generation spectra show significant asymmetry for negative versus neutral/positive electrode charge conditions.
Article
Chemistry, Multidisciplinary
Rahul Gera, Huib J. Bakker, Ricardo Franklin-Mergarejo, Uriel N. Morzan, Gabriele Falciani, Luca Bergamasco, Jan Versluis, Indraneel Sen, Silvia Dante, Eliodoro Chiavazzo, Ali A. Hassanali
Summary: This study investigates the properties of the water and surfactant C12E6 interface, finding that the addition of C12E6 near the critical micelle concentration enhances hydrogen bond strength and alters the orientation of water molecules. This leads to the formation of a broad interface with a large electric field, potentially opening up new possibilities for designing catalytic and light-harvesting systems at the water-surfactant-air interface.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Review
Spectroscopy
Mason B. Gardner, Brent R. Westbrook, Ryan C. Fortenberry, Timothy J. Lee
Summary: The CcCR quartic force field methodology is capable of computing rotational constants and vibrational frequencies with high precision, with deviations as low as 0.14% and 0.12% from experimental values, making it an accurate approach for spectroscopic data calculations.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2021)
Article
Chemistry, Physical
Giovanni Bressan, Jasper J. van Thor
Summary: This study presents an analytical expression to describe the orientational part of molecular response, which is evaluated for different conditions. Results obtained in the strong-field conditions suggest that careful analysis of two-dimensional spectroscopic experimental data should include laser pulse intensity considerations.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Review
Chemistry, Organic
Toby Lewis-Atwell, Piers A. Townsend, Matthew N. Grayson
Summary: This review examines the performances of different force fields in conformational analysis and organic molecule searching. Some force fields like MM2, MM3, and MMFF94 have shown strong performances, while UFF performed poorly. More comparisons and research are needed in the field of conformational searching.
Article
Chemistry, Physical
Jessica Bowles, Sascha Jahnigen, Rodolphe Vuilleumier, Florent Calvo, Carine Clavaguera, Federica Agostini
Summary: The vibrational spectrum of alanine amino acid was computationally determined in different environments and phases using molecular dynamics trajectories and an optimized polarizable force field. The analysis revealed significant differences between the spectra of neutral and zwitterionic forms of alanine in the gas phase, and provided insights into the molecular origins of vibrational bands in condensed phases.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Chunyu Li, Juan Carlos Verduzco, Brian H. Lee, Robert J. Appleton, Alejandro Strachan
Summary: The response of materials to shock loading is crucial for planetary science, aerospace engineering, and energetic materials. Deep learning is used to predict the resulting shock-induced temperature fields in composite materials, achieving higher accuracy and lower computation cost compared to current state of the art techniques.
NPJ COMPUTATIONAL MATERIALS
(2023)
Article
Polymer Science
Natalia Lukasheva, Dmitry Tolmachev, Hector Martinez-Seara, Mikko Karttunen
Summary: Electrostatic interactions play a crucial role in the behavior of polyelectrolyte molecules. This study investigated the behavior of anionic polyelectrolytes in water solutions using molecular dynamics simulations. Comparisons were made between different force fields, and the limitations and strengths of these force fields were determined based on experimental data. The results showed that the size and dynamics of the molecules depend on the models for the counterions, and the local structures and dynamics are sensitive to dihedral angle parameterization. Recommendations were made based on the findings.
Article
Chemistry, Physical
Brajesh Narayan, Colm Herbert, Brian J. Rodriguez, Bernard R. Brooks, Nicolae-Viorel Buchete
Summary: The study investigates the temperature-dependent conformational dynamics of FF peptides solvated in water molecules using replica exchange molecular dynamics (REMD) simulations. External electric fields may introduce artifacts in REMD simulations of solvated peptides, but can be corrected by adjusting the initial conditions. Results indicate that the thermodynamic and kinetic properties of small FF amyloid peptides can be altered by both temperature and electric fields.
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)
Article
Chemistry, Physical
Yujing Wei, Artem G. G. Volosniev, Dusan Lorenc, Ayan A. A. Zhumekenov, Osman M. M. Bakr, Mikhail Lemeshko, Zhanybek Alpichshev
Summary: Rotating organic cations and dynamically disordered soft inorganic cages are the defining features of organic-inorganic lead-halide perovskites. This study investigates the interplay between these two subsystems by using the polarizability of the organic cation as a sensitive probe of the local crystal fields. The results obtained through infrared spectroscopy provide insights into the motion of the cation molecule, the magnitude of the local crystal field, and the strength of the hydrogen bond.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Biochemistry & Molecular Biology
Giulia Giubertoni, Federico Caporaletti, Steven J. Roeters, Adam S. Chatterley, Tobias Weidner, Peter Laity, Chris Holland, Sander Woutersen
Summary: The mechanical properties of biomaterials are influenced by the interactions and conformations of their protein building blocks. Infrared spectroscopy is a commonly used method for studying molecular structures, and polarized two-dimensional infrared spectroscopy (2D-IR) is applied in this study to identify the protein secondary structures in native silk films. The results show changes in the secondary structure due to hydration, with an increase in random coil content and a decrease in helical content.
Article
Chemistry, Multidisciplinary
Sejun An, Dabin Kim, Junggil Kim, Sang Kyu Kim
Summary: We report the first experimental observation of the excited dipole-bound state of cryogenically cooled nitromethane anion, and investigate the Feshbach resonances and anionic clusters using photofragment and photodetachment action spectra.
Article
Chemistry, Multidisciplinary
Clemens Mueller, Kevin Scholten, Elric Engelage, Christian Merten
Summary: In this study, the conformational preferences of a series of chiral octaazacryptands were investigated using experimental and computational techniques. The results indicate that these octaazacryptands prefer a collapsed structure in solution.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Physics, Multidisciplinary
Michael Yannai, Yuval Adiv, Raphael Dahan, Kangpeng Wang, Alexey Gorlach, Nicholas Rivera, Tal Fishman, Michael Kruger, Ido Kaminer
Summary: The ability to form monoenergetic electron beams is crucial for high-resolution electron spectroscopy and imaging. In this study, a lossless monochromator mechanism for electron energy monochromation is developed, which utilizes the interaction of free-electron pulses with single-cycle THz near fields. The experiment successfully reduces the electron energy spread without compromising the beam flux, demonstrating the robustness and wide tunability of the technique. The findings have direct applications in ultrafast electron microscopy, enabling time- and energy-resolved studies in various areas.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Physical
Padmabati Mondal, Pierre-Andre Cazade, Akshaya K. Das, Tristan Bereau, Markus Meuwly
Summary: The dynamics and spectroscopy of N-methyl-acetamide and trialanine in solution were characterized using different energy functions, with MTP and FNM methods showing better agreement with experiments compared to PC methods. The conformational ensemble sampled from simulations using PCs is consistent with literature, while that covered by MTP-based simulations is dominated by P-II with contributions from beta and alpha(R).
JOURNAL OF PHYSICAL CHEMISTRY B
(2021)