Article
Chemistry, Multidisciplinary
Alexander S. Frolov, Carolien Callaert, Maria Batuk, Joke Hadermann, Andrey A. Volykhov, Anna P. Sirotina, Matteo Amati, Luca Gregoratti, Lada Yashina
Summary: This study investigates the reaction between the GeTe (111) surface with molecular oxygen, focusing on crystals with sole inversion domains. The reaction kinetics and structure of the oxide layer are evaluated, revealing nanoscale phase separation of GeO2 and Te, which is unusual for semiconductors.
Article
Chemistry, Physical
Paul L. Houston, Chen Qu, Apurba Nandi, Riccardo Conte, Qi Yu, Joel M. Bowman
Summary: Researchers have recently made further improvements to permutationally invariant polynomial (PIP) regression, including compacting purified basis and speeding up gradient evaluation using reverse differentiation method. They found that PIP computation time for energy and force evaluation is significantly faster than other machine-learning methods, and have introduced a new PIP potential energy surface (PES) for ethanol.
JOURNAL OF CHEMICAL PHYSICS
(2022)
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
Physics, Applied
Q. Wang, B. Zhai, H. P. Wang, B. Wei
Summary: This study extended the development of deep neural network potential for liquid Nb5Si3, revealing the structural features, chemical short-range order parameter, and dynamic properties of the liquid alloy. Large amounts of fivefold symmetry Honeycutt-Andersen pairs were identified in high-temperature melts, but icosahedral symmetry and distorted icosahedrons accounted for a small proportion according to Voronoi polyhedron analysis, influenced by thermal motion. In addition to documented distorted ICOs, six more quasi-ICOs were identified to deform from ICOs at high temperatures.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Chemistry, Physical
Koushik Naskar, Satyam Ravi, Satrajit Adhikari, Michael Baer, Narayanasami Sathyamurthy
Summary: First-principles based beyond Born-Oppenheimer theory is used to construct multistate global Potential-Energy Surfaces (PESs) for the HeH2+ system by explicitly incorporating the Nonadiabatic Coupling Terms (NACTs). Adiabatic PESs and NACTs for the lowest four electronic states (12A ', 22A ', 32A ' and 42A ') are evaluated as functions of hyperangles in hyperspherical coordinates. Conical intersections between different states are validated by integrating the NACTs along chosen contours. Subsequently, adiabatic-to-diabatic (ADT) transformation angles are determined to construct the diabatic potential matrix, which is suitable for accurate scattering calculations.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Physical
Feina Zhai, Yun Tian, Dandan Song, Yuanjie Li, Xiaojing Liu, Ting Li, Zhaojun Zhang, Xiangjian Shen
Summary: An in-depth understanding of the interactions between hydrogen and transition metal catalysts is crucial for exploring novel heterogeneous hydrogenation reaction mechanisms. This study comprehensively investigates the interactions of hydrogen on active metal surfaces, revealing differences between Ni-group and Cu-group transition metals and the effects of reaction temperature and hydrogen partial pressure on stable adsorption phase diagrams. Additionally, the evolution of metal nanoparticles under moderate reaction conditions differs between Ni-group and Cu-group metals.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Physical
Ryan Gotchy Mullen, Nir Goldman
Summary: Hydriding corrosion of plutonium causes surface cracking, pitting, and structural failure. This study calculates the surface energies of low facet surfaces of face-centered cubic delta-Pu, and discusses the adsorption free energies of hydrogen structures at different coverage levels, as well as the progression of filling sites with increasing H-2 partial pressure. Implications for near-equilibrium pressure hydride nucleation and non-equilibrium millibar pressure hydriding are explored.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Nanoscience & Nanotechnology
Changle Li, Song Lu, Levente Vitos
Summary: A robust method for estimating grain boundary energies for complex multicomponent alloys is introduced, using surface energy as the input parameter easily accessible through modern ab initio calculations. The method is demonstrated in the case of paramagnetic Fe-Cr-Ni alloys with available experimental grain boundary data, showcasing its effectiveness.
SCRIPTA MATERIALIA
(2021)
Article
Nanoscience & Nanotechnology
Hwanyeol Park, Dong-Hoon Han, Hong Taek Lim, Woojin Choi, Ho Jun Kim
Summary: This study investigates the thermodynamic driving force and phase transition mechanism of tungsten-alumina heterostructures using first-principles methods. The results show that amorphous tungsten films maintain a conformal coverage at nanoscale (0.7 nm) until the thickness exceeds this value.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Inorganic & Nuclear
Tiago F. C. Cruz, Luis F. Veiros, Pedro T. Gomes
Summary: A well-defined single-component manganese(II) catalyst system for the hydrosilylation of aldehydes and ketones is presented. Complexes 1 and 2 were synthesized and characterized, with complex 2 proving to be highly active for the hydrosilylation of various aldehydes and ketones under mild conditions.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Nisha K. Agrawal, S. Gayathridevi, Soumya R. Dash, Kumar Vanka, Balaji R. Jagirdar
Summary: Treatment of trans-[Ir(H)(N)(2)((iPr)4)(POCOP)(DMAP)][BAr4f] with H-2 under ambient conditions resulted in the formation of trans-[Ir(H)(?(2)-H-2)((iPr)4)(POCOP)(DMAP)][BAr4f]. Computational studies suggest that the exchange of hydrogen atoms between H-2 and the hydride ligands involves metal-ligand cooperativity.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Daniele Belletto, Fortuna Ponte, Nico Sanna, Stefano Scoditti, Emilia Sicilia
Summary: The computational investigation of a recently synthesized monofunctional Pt-II complex that selectively interacts with G-Q structures has revealed key steps in the mechanism of action, providing insights for designing more effective anti-cancer drugs.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Physical
Jessica A. Martinez, Lukas Paetow, Johannes Tolle, Xuecheng Shao, Pablo Ramos, Johannes Neugebauer, Michele Pavanello
Summary: Understanding and predicting the properties of molecular liquids is difficult due to cooperative behavior among the molecules. In this study, we analyze the ionization potential (IP) of liquid water by dissecting its contributions from individual molecules using periodic subsystem DFT. We identify and evaluate four electronic contributions to the IP: mean-field, electronic correlation, interaction with and polarization of the environment. We also analyze their impact on the IP relative to the structural fluctuation of liquid water.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Chemistry, Physical
Sandip Ghosh, Tapas Sahoo, Michael Baer, Satrajit Adhikari
Summary: This study analyzed the dynamics of the H + H-2(+) reaction from the electronically first excited state using diabatic potential energy surfaces constructed by employing the Beyond Born-Oppenheimer theory. The research extensively investigated charge transfer processes, calculated state-to-state probabilities, and compared temperature-dependent rate constants with experimental measurements.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Chemistry, Physical
Roberto Cammi, Bo Chen
Summary: In this study, we propose a new theory for investigating the potential energy surface of compressed molecular systems. By using a Legendre transform, we derive an analytical expression for the gradient of the total energy, which can be used for optimizing the geometries of compressed molecular systems. Additionally, we demonstrate that the potential energy surface can be explicitly studied as a function of pressure, and it is connected to the well-known Hammond postulate.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Dora Papp, Viktor Tajti, Gustavo Avila, Edit Matyus, Gabor Czako
Summary: The automated development of a new ab initio full-dimensional potential energy surface (PES) for the CH4 · F- complex using the Robosurfer program package is reported. The new potential provides a near-spectroscopic quality description over a broad configuration range, including the dissociation and vibrations of methane. Full-dimensional (12D) variational vibrational computations using the new PES show the presence of tunnelling splittings larger than 0.1 cm(-1) below the top of the interconversion barrier of the complex's four equivalent minima.
Article
Chemistry, Physical
Tibor Gyori, Gabor Czako
Summary: Reactions between methanol and the hydroxyl radical have important implications in combustion, atmospheric, and astrochemistry. While previous studies have focused on the formation of H2O as the primary products, this research explores other potential products. Through comprehensive thermochemical calculations and evaluations, it was found that the formation of methanediol and the hydroxymethoxy radical is favorable, and the endothermicity of formaldehyde formation is low, making it a possible product channel. The study also observed unexpected energy deviations between different computational methods.
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
Chemistry, Physical
Cangtao Yin, Gabor Czako
Summary: A quasi-classical trajectory study was conducted for the multi-channel reaction between HBr and C2H5. The effect of different vibrational modes of reactants on reactivity and energy flow was investigated. It was found that the reaction was significantly less reactive when the HBr-stretching mode was excited, but all reaction pathways were promoted when this mode was excited. The excitation of C2H5 had no clear promotion effect except for the H-exchange process. The excitation in the HBr vibrational mode was more effective than increasing translational energy. The forward scattering mechanism was promoted by the HBr-stretching mode or high collision energy, indicating the dominance of the direct stripping mechanism. At low collision energy with no excitation or excitation of any C2H5 vibrational mode, the forward scattering feature was less obvious. When the HBr-stretching mode was excited, the product gained more relative translational energy, but when the excitation was in C2H5, the product gained less relative translational energy compared to the ground-state reaction.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Domonkos Tasi, Tim Michaelsen, Roland Wester, Gabor Czako
Summary: This study investigates the dynamics of the OH- + CH3I reaction using high-level quasi-classical trajectory simulations. Comparisons with reanalysed crossed-beam ion imaging experiments show better agreement between the revised experiment and theoretical results. Additionally, benchmark geometries, frequencies, and relative energies of stationary points are determined for the proton-abstraction and S(N)2 channels in the OH- + CH3I reaction.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Balazs Gruber, Gabor Czako
Summary: This study systematically searched the transition-state and product-channel complex regions of the OH + glycine reactions and found different conformers. All reactions are exothermic and proceed via shallow barriers.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Astronomy & Astrophysics
Sarah Nickerson, Naseem Rangwala, Sean W. J. Colgan, Curtis DeWitt, Jose. S. S. Monzon, Xinchuan Huang, Kinsuk Acharyya, Maria. N. N. Drozdovskaya, Ryan. C. C. Fortenberry, Eric Herbst, Timothy. J. J. Lee
Summary: This study presents the first high spectral resolution mid-infrared survey in the Orion BN/KL region, identifying two new kinematic components with chemically rich molecular absorption lines. The findings provide in-depth insights into the physical conditions and molecular emission lines associated with the blue and red clumps. The study also supports the idea that these clumps are distinct components unrelated to the classic components in the Orion BN/KL region.
ASTROPHYSICAL JOURNAL
(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
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
Chemistry, Physical
Cangtao Yin, Gabor Czako
Summary: We investigated the mode-specificity of the HI + C2H5 reaction by exciting four different vibrational modes of the reactants and studying the effect on reactivity, mechanism, and energy transfer. Exciting the HI-stretching mode strongly promotes both reaction pathways, while excitations on C2H5 surprisingly inhibit the dominant H-abstraction pathway. The dominance of direct stripping mechanism and direct rebound mechanism is observed in H-abstraction and I-abstraction, respectively.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Andras B. Nacsa, Mate Kigyosi, Gabor Czako
Summary: The potential energy surfaces of serine and its protonated counterparts were investigated to determine the structures of the minima. Various calculations were performed to determine the relative energies, geometries, and vibrational frequencies. Additionally, thermodynamic values, such as proton affinity and gas-phase basicity, were calculated considering different protonation sites.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Boldizsar Ballay, Timea Szucs, Dora Papp, Gabor Czako
Summary: In this study, we use advanced electronic structure methods to determine the energies and geometries of relevant key points in the X- + PH2Y reactions. We analyze the main reaction routes and product channels, taking into account various corrections to obtain accurate results.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Cangtao Yin, Gabor Czako
Summary: The global full-dimensional potential energy surface (PES) for the reaction of the Criegee intermediate, CH2OO, with the NH3 molecule is developed using different ab initio methods. The accuracy of the PES is confirmed by comparing its properties with ab initio data. Quasi-classical trajectory simulations are used to calculate reaction probabilities and cross sections. The study reveals that the maximum impact parameter for reactivity is independent of collision energy, and the reaction probability increases with increasing collision energy for this negative-barrier reaction.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Cangtao Yin, Gabor Czako
Summary: In this study, a full-dimensional spin-orbit-corrected analytical coupled-cluster-quality potential energy surface (PES) is developed. Quasi-classical trajectory (QCT) simulations are performed to investigate the HI + C2H5 -> I + C2H6 reaction. The results show the collision energy dependence of reaction probability, scattering angle distribution, and attack preference at different attack sites.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Timea Szucs, Gabor Czako
Summary: This electronic structure study investigates the reaction pathways of the F + CH3NH2 system, revealing four exothermic and two endothermic reactions. The study provides insights into the hydrogen abstraction, substitution, and hydrogen substitution reactions in this system.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
