State-to-state inelastic rotational cross sections in five-atom systems with the multiconfiguration time dependent Hartree method

被引:8
作者
Ndengue, Steve [1 ,2 ]
Scribano, Yohann [3 ]
Gatti, Fabien [4 ]
Dawes, Richard [2 ]
机构
[1] Univ Rwanda, ICTP East African Inst Fundamental Res, Kigali, Rwanda
[2] Missouri Univ Sci & Technol, Dept Chem, Rolla, MO 65409 USA
[3] Univ Montpellier, UMR CNRS 5299, Lab Univers & Particule Montpellier, F-34095 Montpellier, France
[4] Univ Paris Saclay, Univ Paris Sud, Inst Sci Mol Orsay, UMR 8214, F-91405 Orsay, France
关键词
COLLISIONAL EXCITATION RATES; GENERAL-ASPECTS; LOW-TEMPERATURE; H2O; H-2; DYNAMICS; SCATTERING; PARA-H-2; ROTOR; WATER;
D O I
10.1063/1.5119381
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
We present a MultiConfiguration Time Dependent Hartree (MCTDH) method as an attractive alternative approach to the usual quantum close-coupling method that approaches some computational limits in the calculation of rotational excitation (and de-excitation) between polyatomic molecules (here collisions between triatomic and diatomic rigid molecules). We have performed a computational investigation of the rotational (de-)excitation of the benchmark rigid rotor H2O-H-2 system on a recently developed Potential Energy Surface of the complex using the MCTDH method. We focus here on excitations and de-excitations from the 0(00), 1(11), and 1(10) states of H2O with H-2 in its ground rotational state, looking at all the potential transitions in the energy range 1-200 cm(-1). This work follows a recently completed study on the H2O-H-2 cluster where we characterized its spectroscopy and more generally serves a broader goal to describe inelastic collision processes of high dimensional systems using the MCTDH method. We find that the cross sections obtained from the MCTDH calculations are in excellent agreement with time independent calculations from previous studies but does become challenging for the lower kinetic energy range of the de-excitation process: that is, below approximately 20 cm(-1) of collision energy, calculations with a relative modest basis become unreliable. The MCTDH method therefore appears to be a useful complement to standard approaches to study inelastic collision for various collision partners, even at low energy, though performing better for rotational excitation than for de-excitation.
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页数:11
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共 40 条
[1]   The multiconfiguration time-dependent Hartree (MCTDH) method:: a highly efficient algorithm for propagating wavepackets [J].
Beck, MH ;
Jäckle, A ;
Worth, GA ;
Meyer, HD .
PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS, 2000, 324 (01) :1-105
[2]   Low-Energy Water-Hydrogen Inelastic Collisions [J].
Bergeat, Astrid ;
Faure, Alexandre ;
Morales, Sebastien B. ;
Moudens, Audrey ;
Naulin, Christian .
JOURNAL OF PHYSICAL CHEMISTRY A, 2020, 124 (02) :259-264
[3]   QUANTUM DYNAMICS OF NON-RIGID SYSTEMS COMPRISING 2 POLYATOMIC FRAGMENTS [J].
BROCKS, G ;
VANDERAVOIRD, A ;
SUTCLIFFE, BT ;
TENNYSON, J .
MOLECULAR PHYSICS, 1983, 50 (05) :1025-1043
[4]   PSEUDOSPECTRAL METHOD FOR SOLVING THE TIME-DEPENDENT SCHRODINGER-EQUATION IN SPHERICAL COORDINATES [J].
COREY, GC ;
LEMOINE, D .
JOURNAL OF CHEMICAL PHYSICS, 1992, 97 (06) :4115-4126
[5]   Influence of collisional rate coefficients on water vapour excitation [J].
Daniel, F. ;
Goicoechea, J. R. ;
Cernicharo, J. ;
Dubernet, M. -L. ;
Faure, A. .
ASTRONOMY & ASTROPHYSICS, 2012, 547
[6]   Influence of a new potential energy surface on the rotational (de)excitation of H2O by H2 at low temperature [J].
Dubernet, M. -L. ;
Daniel, F. ;
Grosjean, A. ;
Faure, A. ;
Valiron, P. ;
Wernli, M. ;
Wiesenfeld, L. ;
Rist, C. ;
Noga, J. ;
Tennyson, J. .
ASTRONOMY & ASTROPHYSICS, 2006, 460 (01) :323-329
[7]   Rotational excitation of ortho-H2O by para-H2 (j2=0, 2, 4, 6, 8) at high temperature [J].
Dubernet, M. -L. ;
Daniel, F. ;
Grosjean, A. ;
Lin, C. Y. .
ASTRONOMY & ASTROPHYSICS, 2009, 497 (03) :911-925
[8]   Collisional excitation rates of H2O with H2 -: I.: Pure rotational excitation rates with para-H2 at very low temperature [J].
Dubernet, ML ;
Grosjean, A .
ASTRONOMY & ASTROPHYSICS, 2002, 390 (02) :793-800
[9]   Quasi-classical rate coefficient calculations for the rotational (de) excitation of H2O by H2 [J].
Faure, A. ;
Crimier, N. ;
Ceccarelli, C. ;
Valiron, P. ;
Wiesenfeld, L. ;
Dubernet, M. L. .
ASTRONOMY & ASTROPHYSICS, 2007, 472 (03) :1029-1035
[10]   Collisional excitation of water in warm astrophysical media I. Rate coefficients for rovibrationally excited states [J].
Faure, A. ;
Josselin, E. .
ASTRONOMY & ASTROPHYSICS, 2008, 492 (01) :257-264