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Related papers: Rotational Energy Transfer in H2+H2

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We present a first principles-quality potential energy surface (PES) describing the inter-atomic forces for hydrogen atoms interacting with free-standing graphene. The PES is a high-dimensional neural network potential that has been…

We present comprehensive \textsl{ab initio} calculations of CO$_{\rm 2}$-H$_{\rm 2}$ and CO$_{\rm 2}$-He collisional properties from first principles, employing CCSD(T), potential calculations together with close-coupling dynamical…

Transition state theory was introduced in the 1930s to account for chemical reactions. Central to this theory is the idea of a potential energy surface (PES). It was assumed that such a surface could be constructed using eigensolutions of…

Quantum Physics · Physics 2015-06-05 Brian T. Sutcliffe , R. Guy Woolley

The charge transfer in low energy (0.25 to 150 eV/amu) H($nl$) + He$^+(1s)$ collisions is investigated using a quasi-molecular approach for the $n=2,3$ as well as the first two $n=4$ singlet states. The diabatic potential energy curves of…

Quantum Physics · Physics 2015-05-19 J. Loreau , K. Sodoga , D. Lauvergnat , M. Desouter-Lecomte , N. Vaeck

We present a 3D isotropic ab initio three-body (para-H$_2$)$_3$ interaction potential energy surface (PES). The electronic structure calculations are carried out at the correlated coupled-cluster theory level, with single, double, and…

Chemical Physics · Physics 2025-06-05 Alexander Ibrahim , Pierre-Nicholas Roy

The H$_2$+H$_2$ system has long been considered as a benchmark system for ro-vibrational energy transfer in bimolecular collisions. However, most studies thus far have focused on collisions involving H$_2$ molecules in the ground…

Chemical Physics · Physics 2022-12-20 James F. E. Croft , Pablo G. Jambrina , F. Javier Aoiz , Hua Guo , N. Balakrishnan

Rates for rotational excitation of HC3N by collisions with He atoms and H2 molecules are computed for kinetic temperatures in the range 5-20K and 5-100K, respectively. These rates are obtained from extensive quantum and quasi-classical…

Chemical Physics · Physics 2009-11-13 Michael Wernli , Laurent Wiesenfeld , Alexandre Faure , Pierre Valiron

A five-dimensional coupled states (5D-CS) approximation is used to compute cross sections and rate coefficients for CO+H2 collisions. The 5D-CS calculations are benchmarked against accurate six-dimensional close-coupling (6D-CC)…

Instrumentation and Methods for Astrophysics · Physics 2017-01-20 Christina Castro , Kyle Doan , Michael Klemka , Robert C. Forrey , B. H. Yang , Phillip C. Stancil , N. Balakrishnan

We present an isotropic ab initio (para-H$_2$)$_4$ four-body interaction potential energy surface (PES). The electronic structure calculations are performed at the correlated coupled-cluster theory level, with single, double, and…

Chemical Physics · Physics 2025-06-09 Alexander Ibrahim , Pierre-Nicholas Roy

Modeling environments that are not in local thermal equilibrium, such as protoplanetary disks or planetary atmospheres, with molecular spectroscopic data from space telescopes requires knowledge of the rate coefficients of rovibrationally…

Atomic Physics · Physics 2023-10-10 Taha Selim , Ad van der Avoird , Gerrit C. Groenenboom

State-to-state differential cross sections (DCSs) for rotationally inelastic scattering of H2O by H2 have been measured at 71.2 meV (574 cm-1) and 44.8 meV (361 cm-1) collision energy using crossed molecular beams combined with velocity map…

Chemical Physics · Physics 2015-05-27 C-H. Yang , G. Sarma , D. H. Parker , J. J ter Meulen , L. Wiesenfeld

Accurate potential energy surfaces (PESs) have been determined for the $^3$A$'$ and $^3$A$''$ states of N$_2$O using electronic structure calculations at the multireference configuration interaction level with Davidson correction (MRCI+Q)…

Chemical Physics · Physics 2020-11-06 Debasish Koner , Juan Carlos San Vicente Veliz , Raymond J. Bemish , Markus Meuwly

We report elastic and inelastic cross sections for fast superthermal $^{12}$C($^3P$) and $^{13}$C($^3P$) atoms scattering on $^{12}$CO$_2$. The cross sections were computed using quantum-mechanical rotationally close-coupling formalism with…

Earth and Planetary Astrophysics · Physics 2023-08-11 Marko Gacesa

The rise of machine learning has greatly influenced the field of computational chemistry, and that of atomistic molecular dynamics simulations in particular. One of its most exciting prospects is the development of accurate,…

Chemical Physics · Physics 2023-06-14 Silvan Käser , Markus Meuwly

The structure and dynamics of a molecular system is governed by its potential energy surface (PES), representing the total energy as a function of the nuclear coordinates. Obtaining accurate potential energy surfaces is limited by the…

Chemical Physics · Physics 2023-09-29 Karl P. Horn , Luis Itza Vazquez-Salazar , Christiane P. Koch , Markus Meuwly

We present the first fully ab initio calculations of collision-induced broadening and shift of spectral lines in antiprotonic helium ($\bar{p}$He$^{+}$) perturbed by atomic helium. To overcome critical limitations of previous studies, we…

A very accurate, (HF)$_2$ potential energy surface (PES) due to Huang et al. (J. Chem. Phys., 150, 154302 (2019)) is used to calculate the energy levels of the HF dimer by solving the nuclear-motion Schr\"{o}dinger equation using…

Full-dimensional quantum scattering calculations are reported for ro-vibrational transitions in HD+HD collisions using a highly accurate interaction potential for the H$_2$-H$_2$ system. Several near-resonant ro-vibrational transitions are…

Atomic Physics · Physics 2026-03-06 Bikramaditya Mandal , Hubert Jóźwiak , Piotr Wcisło , Naduvalath Balakrishnan

We present a six-dimensional potential energy surface for the H2-H2 dimer based on ab initio electronic structure calculations. The surface is intended to describe accurately the bound and quasibound states of the dimers H2-H2, D2-D2, and…

Chemical Physics · Physics 2009-11-13 Robert J. Hinde

We construct the velocity map images of the proton transfer reaction between helium and molecular hydrogen ions H2+. We perform simulations of imaging experiments at one representative total collision energy taking into account the inherent…

Chemical Physics · Physics 2018-01-17 Mario Hernández Vera , R. Wester , F. A. Gianturco