Article
Chemistry, Physical
Silvan Kaser, Markus Meuwly
Summary: The rise of machine learning has greatly influenced computational chemistry and atomistic molecular dynamics simulations, especially in the development of accurate potential energy surfaces (PESs) for molecules and clusters. Transfer learning offers a data efficient alternative to improve global PESs from lower to higher levels of theory. This work demonstrates that transfer learning can achieve high-quality results for H-transfer barrier energies, harmonic frequencies, and H-transfer tunneling splittings, even with a lower level model like Hartree-Fock theory and a double-zeta basis set.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Peter M. Felker, Yang Liu, Jun Li, Zlatko Bacic
Summary: This study reports full-dimensional and fully coupled quantum calculations of the inter- and intramolecular vibrational states of three isotopologues of the hydrogen chloride-water dimer. The research extends previous investigations and highlights the significant impact of isotopic variations on the vibrational properties.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Chemistry, Physical
Peter M. Felker, Zlatko Bacic
Summary: In this study, quantum five-dimensional bound-state calculations were conducted to investigate the fully coupled intermolecular rovibrational states of H2O-CO2 and D2O-CO2 complexes. The results provide a comprehensive description of the intermolecular rovibrational level structure and show good agreement with experimental data.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
P. Soulard, B. Tremblay
Summary: The investigation of water molecule complexed with CS2 molecule in solid neon was performed using Fourier transform infrared spectroscopy, identifying several vibrational transitions and determining the structures of the observed complexes through theoretical calculations at the MP2 level and comparison with experimental data.
JOURNAL OF MOLECULAR STRUCTURE
(2021)
Article
Chemistry, Multidisciplinary
Zhiqiang Guo, Xiaoxuan Fan, Xiaokun Wen, Wen Liu, Baijie Guan, Xia Hong, Kexin Wang, Jiwei Wang
Summary: An anomalous solvent-induced luminescence quenching of NH2-MIL-53(Fe) in D2O is reported. This quenching is not caused by protonation or high-frequency vibrations of solvent molecules, but due to the inhibition of charge transfer by hydrogen bonding between NH2-MIL-53(Fe) and D2O. This discovery enables accurate quantitative detection of specific volume fractions of D2O in H2O.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Chenxing Liang, Archith Rayabharam, N. R. Aluru
Summary: In this study, the structural and dynamical properties of water and heavy water under nanoscale confinement were investigated using path integral molecular dynamics simulations. It was found that under nanoscale confinement, the bond length and bond angle of both water and heavy water were smaller compared to the bulk state. The number of hydrogen bonds decreased, indicating a weakened hydrogen bond interaction. Heavy water had a higher dipole moment and stronger hydrogen bonding than water.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Chemistry, Physical
Cangtao Yin, Viktor Tajti, Gabor Czako
Summary: This study reports a spin-orbit-corrected analytical potential energy surface for the HBr + C2H5 -> Br + C2H6 reaction and investigates the reaction dynamics using quasi-classical methods. The simulation results show that the reaction probability exhibits a non-monotonic dependence on collision energy and is influenced by the attack angle and approach direction.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Eric R. Heller, Jeremy O. Richardson
Summary: This study simulates two recent matrix-isolation experiments at cryogenic temperatures, revealing the failure of the commonly used weak-coupling method in describing deep-tunneling reactions. However, the more rigorous approach of semiclassical golden-rule instanton theory combined with double-hybrid density-functional theory and multireference perturbation theory successfully reproduces rate constants and kinetic isotope effects in good agreement with experiment. Additionally, these calculations identify the optimal tunnelling pathways, providing a molecular picture of the reaction mechanism.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Applied
Thibault Pariat, Pauline M. Verite, Denis Jacquemin, Julien Massue, Gilles Ulrich
Summary: A dual-emissive fluorophore, HBBODipic, with an Excited-State Intramolecular Proton Transfer (ESIPT) process has been described. It has been used for generating panchromatic white-emission and ratiometric detection of substrates.
Article
Nanoscience & Nanotechnology
B. Akdim, C. Woodward, S. Rao, E. Antillon
Summary: Recent studies have shown that chemically-complex solid-solution alloys produce equilibrium dislocations at high temperatures, leading to kinks and pinning points that significantly increase strength. Atomistic studies and chemical analysis can help understand the effects of different alloy compositions on dislocation formation.
SCRIPTA MATERIALIA
(2021)
Article
Chemistry, Physical
Dan Hou, Yu Zhai, Ting-Ting Sun, Xiao-Long Zhang, Hui Li
Summary: The ab initio potential energy surfaces (PESs) for the H2O-Ne system with explicit consideration of the intramolecular overtone state of H2O were obtained. Vibrationally averaged intermolecular potentials were calculated and used to predict rovibrational energy levels and transitions, with good agreement with experimental data. These results provide reliable theoretical guidance for future infrared overtone spectroscopy of clusters.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Ruinian Xu, Ning Liu, Chengna Dai, Yan Li, Jie Zhang, Bin Wu, Gangqiang Yu, Biaohua Chen
Summary: By introducing H2O molecules on Cu-BEA zeolites, the selectivity, productivity, and long-term stability of direct oxidation of methane to methanol can be significantly improved.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Optics
Vladimir Tyuterev, Alain Barbe, Semen Mikhailenko, Evgeniya Starikova, Yurii Babikov
Summary: Accurate knowledge of line parameters and intensities is crucial for measuring ozone concentration in the atmosphere, and ab initio calculations have shown to be effective in achieving consistency in measurements and databases. This paper extends ab initio corrections to ozone band intensities in a wider infrared range, correcting about 40% of intensities for various ozone isotopologues. The resulting line list is now available online and will be used in the future HITRAN20 update.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2021)
Article
Chemistry, Physical
R. Dahmani, S. Grubisic, I Djordjevic, S. Ben Yaghlane, S. Boughdiri, G. Chambaud, M. Hochlaf
Summary: A nitrogen-rich triazole-type Metal-Organic Framework (MOF) called Zinc Triazolate based Framework (ZTF) was proposed for CO2 capture, showing exceptional CO2 uptake capacity and the influence of water molecules on CO2 adsorption. The interactions between CO2 and ZTF surface cavities at a microscopic level were examined, revealing Lewis acid-Lewis base interactions, hydrogen bonding, and electrostatic interactions. Additionally, simulations indicated that the presence of H2O molecules enhances CO2 adsorption at very low pressures but reduces it at higher pressures.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Tatsuya Ishiyama
Summary: NE-AIMD simulations were used to study the vibrational energy relaxation path of excited non-hydrogen-bonded OH at an air/water interface. The simulations reproduced experimentally observed features, showing that relaxation time scales of free OH at the surface of pure water and isotopically diluted water are similar. It was found that both stretching vibrational coupling and bend-stretching combination band contribute to the relaxation path of free OH at the surface.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Kim Steenbakkers, Aravindh N. Marimuthu, Britta Redlich, Gerrit C. Groenenboom, Sandra Bruenken
Summary: We present the first broadband vibrational action spectroscopic investigation of the linear radical cation of cyanoacetylene, HC3N+ ((2)pi), using the infrared pre-dissociation method. The vibronic splitting patterns of the bending modes were fully resolved, revealing previously unobserved bands. Spectroscopic constants obtained from the experimental data are in reasonable agreement with previous studies and ab initio calculations. The influence of the attached Ne atom on the infrared spectrum was also investigated.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Physics, Atomic, Molecular & Chemical
Xinchuan Huang, Richard S. Freedman, Sergey Tashkun, David W. Schwenke, Timothy J. Lee
Summary: AI-3000K is a semi-empirical IR line list that has been upgraded for the analysis and simulation of hot CO2 spectra up to 3000-4000K. It incorporates a new optimization algorithm and includes the latest improvements in PES, DMS, and room temperature IR line list. The accuracy of the line positions and intensities has been significantly improved compared to previous versions.
JOURNAL OF MOLECULAR SPECTROSCOPY
(2023)
Article
Astronomy & Astrophysics
Charles A. Bowesman, Irina I. Mizus, Nikolay F. Zobov, Oleg L. Polyansky, Janos Sarka, Bill Poirier, Marco Pezzella, Sergei N. Yurchenko, Jonathan Tennyson
Summary: New line lists for the D2H+ and D-3(+) isotopologues of H-3(+) have been updated using empirical energy levels and effective Hamiltonian energies. Accurate frequencies for far infrared lines for these species can now be predicted. The energy level assignments of H-3(+) and D-3(+) have been extended using variational calculations and transition intensity analysis. All line lists are available on www.exomol.com.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Thomas Mellor, Alec Owens, Jonathan Tennyson, Sergei N. Yurchenko
Summary: This article presents a comprehensive rotation-vibration line list of thioformaldehyde applicable for elevated temperatures (2000 K). The new MOTY line list covers the 0-8000 cm(-1) range (wavelengths lambda > 1.3 μm) and contains billions of transitions between millions of states with rotational excitation up to J = 120. The line list calculations utilize a newly determined empirically refined potential energy surface, a high-level ab initio dipole moment surface, and an exact kinetic energy operator for solving the ro-vibrational Schrodinger equation. Post-processing of the MOTY line list improves the accuracy of predicted line positions, making it suitable for high-resolution applications. The MOTY line list is available from the ExoMol database and the CDS astronomical database.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Article
Astronomy & Astrophysics
Sergei N. Yurchenko, Emma Nogue, Ala'a A. A. Azzam, Jonathan Tennyson
Summary: This paper presents a line list for two isotopologues of aluminium monochloride, (AlCl)-Cl-35 and (AlCl)-Cl-37, covering the wavelength range below 0.2 μm, J up to 400, and applicable for temperatures up to 5000 K. The line lists are constructed using an empirical spectroscopic model that combines potential energy curves, spin-orbit coupling curves, electronic angular momentum curves, and Born-Oppenheimer breakdown correction curves with ab initio dipole moments, encompassing the four lowest electronic states. The article also addresses the challenges in assigning some laboratory rovibronic spectra and discusses the treatment of states in the continuum.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2023)
Review
Physics, Fluids & Plasmas
Luis L. Alves, Markus M. Becker, Jan van Dijk, Timo Gans, David B. Go, Katharina Stapelmann, Jonathan Tennyson, Miles M. Turner, Mark J. Kushner
Summary: The field of low-temperature plasmas (LTPs) excels by its intellectual diversity, interdisciplinarity, and range of applications. Communication challenges arise due to diverse reporting practices and expectations. This paper addresses these challenges by discussing standards for measurements, diagnostics, computations, reporting, and plasma sources to improve communication and transparency within the LTP field.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Aleksandr A. Balashov, Katarzyna Bielska, Gang Li, Aleksandra A. Kyuberis, Szymon Wojtewicz, Jolanta Domyslawska, Roman Ciurylo, Nikolay F. Zobov, Daniel Lisak, Jonathan Tennyson, Oleg L. Polyansky
Summary: The intensities of 14 lines in the sixth overtone (7-0) band of 12CO are measured using a frequency-stabilized cavity ring-down spectrometer in the visible range. This is the first observation of such a high and weak overtone spectrum of the CO molecule. A theoretical model is constructed and tested based on accurate ab initio dipole moment and semi-empirical potential energy curves. Although the high overtone transitions present a challenge due to their weak lines, agreement between theory and experiment is achieved within a few percent of experimental uncertainty, after addressing issues with the stability of the Davidson correction to the multi-reference configuration interaction calculations.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Biochemistry & Molecular Biology
Megan C. C. Davis, Xinchuan Huang, Ryan C. C. Fortenberry
Summary: This study explores new high-level ab initio quartic force field (QFF) methods that provide spectroscopic data for the electronically excited states of carbon monoxide, water, and formaldehyde cations, which are important in cometary spectral analysis. The QFFs based on equation-of-motion ionization potential (EOM-IP) achieve accurate assignments for the vibrational frequencies of the excited states of the formaldehyde cation. The study also proposes re-assignments for the vibrational frequencies of the water cation based on computational results.
Article
Multidisciplinary Sciences
E. Sierda, X. Huang, D. I. Badrtdinov, B. Kiraly, E. J. Knol, G. C. Groenenboom, M. I. Katsnelson, M. Rosner, D. Wegner, A. A. Khajetoorians
Summary: The study demonstrated a method of simulating molecular orbitals using a solid-state quantum simulator in the laboratory, by positioning cesium atoms on a surface. This approach allowed the creation of artificial atoms, serving as building blocks for artificial molecular structures with different orbital symmetries.
Article
Astronomy & Astrophysics
Sam O. M. Wright, Stevanus K. K. Nugroho, Matteo Brogi, Neale P. P. Gibson, Ernst J. W. de Mooij, Ingo Waldmann, Jonathan Tennyson, Hajime Kawahara, Masayuki Kuzuhara, Teruyuki Hirano, Takayuki Kotani, Yui Kawashima, Kento Masuda, Jayne L. L. Birkby, Chris a. A. Watson, Motohide Tamura, Konstanze Zwintz, Hiroki Harakawa, Tomoyuki Kudo, Klaus Hodapp, Shane Jacobson, Mihoko Konishi, Takashi Kurokawa, Jun Nishikawa, Masashi Omiya, Takuma Serizawa, Akitoshi Ueda, Sebastien Vievard, Sergei N. N. Yurchenko
Summary: Individual vibrational band spectroscopy provides an opportunity to examine exoplanet atmospheres by studying the differences in vibrational state populations of molecules compared to the Boltzmann distribution assumption. This study investigates the detection of OH vibrational bands in exoplanet atmospheres using the hot Jupiter WASP-33b as an example. By simulating low-resolution spectroscopic data and using high-resolution observational data, the authors constructed specific OH cross-section sets and retrieved the vibrational populations from the observed and simulated spectra. The results demonstrate the feasibility of analyzing individual vibrational state populations and reconstructing state population distributions.
ASTRONOMICAL JOURNAL
(2023)
Article
Physics, Atomic, Molecular & Chemical
German Yu. Golubiatnikov, Oleg L. Polyansky, Nikolai F. Zobov, Jonathan Tennyson, Roman I. Ovsyannikov, Mikhail Yu. Tretyakov
Summary: This study performs new measurements of the high-resolution absorption spectrum of H2O-HF dimer using two complementary spectrometers. By refining the positions of the spectral lines and introducing new measurements, it obtains a more accurate set of molecular dynamics constants characterizing the dimer.
JOURNAL OF MOLECULAR SPECTROSCOPY
(2023)
Article
Chemistry, Physical
Xinchuan Huang, David W. Schwenke, Timothy J. Lee
Summary: To analyze data from high-resolution space telescope missions, the BTRHE strategy is used to develop accurate infrared line lists for N2O. The Ames-1 PES is refined using selected HITRAN experimental data, and the Ames-1 DMS is fitted from extrapolated dipoles. Ames-296K line lists are computed for 12 N2O isotopologues, with good agreement shown through comparisons with other intensities.
Article
Optics
Matthias Germann, Adrian Hjalten, Jonathan Tennyson, Sergei N. Yurchenko, Iouli E. Gordon, Christian Pett, Isak Silander, Karol Krzempek, Arkadiusz Hudzikowski, Aleksander Gluszek, Grzegorz Sobon, Aleksandra Foltynowicz
Summary: In this study, optical frequency comb Fourier transform spectroscopy was used to record the spectroscopic data of formaldehyde in a specific frequency range. The line positions and intensities of rovibrational transitions were obtained through line-by-line fitting. By incorporating these accurate line positions into the analysis, more energy levels and rovibrational transitions were predicted with reduced uncertainties in the H2CO spectrum.
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
(2024)
Article
Physics, Fluids & Plasmas
Ramses Snoeckx, Jonathan Tennyson, Min Suk Cha
Summary: Ammonia could play a crucial role as a hydrogen carrier in a decarbonized future and non-thermal plasmas are promising for efficient ammonia production and decomposition processes. This study determined theoretical cross sections for low-energy electron collision processes with ammonia and its radicals using the ab initio R-matrix method. The findings provide insights into dissociation and offer recommended electron collision cross section data for plasma-assisted ammonia production and decomposition processes.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Even Xu, Jonathan Tennyson
Summary: (English Summary:)
This study provides an exhaustive review and comprehensive analysis of the measured rovibrational transitions of the (OCS)-O-16-C-12-S-32 isotopologue of carbonyl sulphide. It recommends a consistent set of harmonic oscillator quantum numbers for future studies. The analysis results in 5729 empirical energy levels, with uncertainties analyzed using different procedures, including the newly implemented bootstrap method.