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Related papers: Rotational Energy Transfer in H2+H2

200 papers

Carbon monoxide is a simple molecule present in many astrophysical environments, and collisional excitation rate coefficients due to the dominant collision partners are necessary to accurately predict spectral line intensities and extract…

Astrophysics of Galaxies · Physics 2015-11-17 Kyle M. Walker , L. Song , B. H. Yang , G. C. Groenenboom , A. van der Avoird , N. Balakrishnan , R. C. Forrey , P. C. Stancil

Results for quantum mechanical calculations of the integral cross sections and corresponding thermal rate coefficients for para-/ortho-H2+HD collisions are presented. Because of significant astrophysical interest in regard to the cooling of…

Chemical Physics · Physics 2015-05-13 Renat A. Sultanov , Avas V. Khugaev , Dennis Guster

Rate coefficients for state-to-state rotational transitions in CO induced by both para- and ortho-H$_2$ collisions are presented. The results were obtained using the close-coupling method and the coupled-states approximation, with the…

Solar and Stellar Astrophysics · Physics 2015-05-18 Benhui Yang , P. C. Stancil , N. Balakrishnan , R. C. Forrey

A new analytical potential energy surface (PES) has been constructed for H$_2^+$-He using a reproducing kernel Hilbert space (RKHS) representation from an extensive number of $ab initio$ energies computed at the multi-reference and full…

Chemical Physics · Physics 2020-07-07 Debasish Koner , Juan Carlos San Vicente Veliz , Ad van der Avoird , Markus Meuwly

Experimental measurements and theoretical calculations of state-to-state rate coefficients for rotational energy transfer of CO in collision with H$_2$ are reported at the very low temperatures prevailing in dense interstellar clouds (5 -…

The dynamics of the reaction H + OH $\to$ O (3P) + H2 have been studied in a series of quasi-classical trajectory (QCT) calculations and transition state theory (TST) methods using high quality 3A' and 3A'' potential energy surfaces (PESs).…

Solar and Stellar Astrophysics · Physics 2014-02-27 Xiaohu Li , Carina Arasa , Marc C. van Hemert , Ewine F. van Dishoeck

Transition intensities for small molecules such as water and CO$_2$ can now be computed with such high accuracy that they are being used to systematically replace measurements in standard databases. These calculations use high accuracy ab…

Aim: We present an improved database of temperature dependent rate coefficients for rotational state-to-state transitions in H$_{2}$O + H$_{2}$O collisions. The database includes 231 transitions between the lower $para$- and 210 transitions…

Chemical Physics · Physics 2023-10-19 Bikramaditya Mandal , Dmitri Babikov

The reaction dynamics for the H + HeH$^+$ $\rightarrow$ He + H$_2^+$ reaction in its electronic ground state is investigated using two different representations of the potential energy surface (PES). The first uses a combined kernel and…

Chemical Physics · Physics 2025-03-28 Meenu Upadhyay , Silvan Käser , Jayakrushna Sahoo , Yohann Scribano , Markus Meuwly

We performed high-dimensional quantum dynamical calculations of the dissociative adsorption and associative desorption of hydrogen on Cu(111). The potential energy surface (PES) is obtained from density functional theory calculations. Two…

mtrl-th · Physics 2009-10-28 A. Gross , B. Hammer , M. Scheffler , W. Brenig

Collisional excitation rate coefficients play an important role in the dynamics of energy transfer in the interstellar medium. In particular, accurate rotational excitation rates are needed to interpret microwave and infrared observations…

Solar and Stellar Astrophysics · Physics 2015-06-10 Benhui Yang , K. M. Walker , R. C. Forrey , P. C. Stancil , N. Balakrishnan

Time-dependent wave packet calculations for the reaction H+HCl and its isotopic reactions are carried out on the potential energy surface (PES) of Bian and Werner (BW2) [Bian, W.; Werner, H. -J., J. Chem. Phys. 2000, 112, 220]. Reaction…

Chemical Physics · Physics 2007-05-23 Li Yao , Ke-Li Han , He-Shan Song , Dong-Hui Zhang

We report new elastic and inelastic cross sections for O($^3P$)+CO$_2$ scattering at collision energies from 0.03 to 5 eV, of major importance to O escape from Mars, Venus, and CO$_2$-rich atmospheres. The cross sections were calculated…

Earth and Planetary Astrophysics · Physics 2021-01-19 Marko Gacesa , Robert J. Lillis , Kevin J. Zahnle

We compute the rotational quenching rates of the first 81 rotational levels of ortho- and para-H2CO in collision with ortho- and para-H2, for a temperature range of 10-300 K. We make use of the quantum close-coupling and coupled-states…

Solar and Stellar Astrophysics · Physics 2015-06-15 Laurent Wiesenfeld , Alexandre Faure

We report combined studies on the prototypical S(^1D_2) + H2 insertion reaction. Kinetics and crossed-beam experiments are performed in experimental conditions approaching the cold energy regime, yielding absolute rate coefficients down to…

A new potential energy surface (PES) and dynamical study are presented of the reactive process between H2CO + OH towards the formation of HCO + H2O and HCOOH + H. In this work a source of spurious long range interactions in symmetry adapted…

Chemical Physics · Physics 2024-06-19 Pablo del Mazo-Sevillano , Alfredo Aguado , Octavio Roncero

We present quantum dynamics of collisions between two para-H2 molecules from low (1 mK) to high collision energies (1 eV). The calculations are carried out using a quantum scattering code that solves the time-independent Schrodinger…

Chemical Physics · Physics 2009-03-18 Goulven Quéméner , Naduvalath Balakrishnan

We present quantum mechanical and quasiclassical trajectory calculations of cross sections for rovibrational transitions in ortho- and para-H_2 induced by collisions with He atoms. Cross sections were obtained for kinetic energies between…

Astrophysics · Physics 2007-05-23 N. Balakrishnan , M. Vieira , J. F. Babb , R. C. Forrey , A. Dalgarno , S. Lepp

We employ an accurate, ab initio potential energy surface (PES) which describes the electronic interaction energy between the molecular anion OH$^-$ ($^1\Sigma^+$) and the neutral rubidium atom Rb ($^2S$), to evaluate the elastic and…

Atomic Physics · Physics 2018-07-31 L. González-Sánchez , F. Carelli , F. A. Gianturco , R. Wester

High-quality potential energy surfaces (PES) are a prerequisite for quantitative atomistic simulations, with both quantum and classical dynamics approaches. The ultimate test for the validity of a PES are comparisons with judiciously chosen…