Nuclear spin dependence of the reaction of H3+ with H2. I. Kinetics and modeling

Kyle N. Crabtree, Brian A. Tom, Benjamin J. McCall
2011 Journal of Chemical Physics  
Articles you may be interested in Radiative charge transfer in He+ + H2 collisions in the milli-to nano-electron-volt range: A theoretical study within state-to-state and optical potential approaches Exact quantum dynamics study of the O + + H 2 ( v = 0 , j = 0 ) → O H + + H ion-molecule reaction and comparison with quasiclassical trajectory calculations Analytical derivatives and non-adiabatic coupling matrix elements are derived for H + n systems (n = 3-5). The method uses a generalized
more » ... a generalized Hellmann-Feynman theorem applied to a multi-state description based on diatomics-in-molecules (for H + 3 ) or triatomics-in-molecules (for H + 4 and H + 5 ) formalisms, corrected with a permutationally invariant many-body term to get high accuracy. The analytical non-adiabatic coupling matrix elements are compared with ab initio calculations performed at multi-reference configuration interaction level. These magnitudes are used to calculate H 2 (v ′ = 0, j ′ = 0) + H + 2 (v, j = 0) collisions, to determine the effect of electronic transitions using a molecular dynamics method with electronic transitions. Cross sections for several initial vibrational states of H + 2 are calculated and compared with the available experimental data, yielding an excellent agreement. The effect of vibrational excitation of H + 2 reactant and its relation with non-adiabatic processes are discussed. Also, the behavior at low collisional energies, in the 1 meV-0.1 eV interval, of interest in astrophysical environments, is discussed in terms of the long range behaviour of the interaction potential which is properly described within the triatomics-in-molecules formalism. C 2015 AIP Publishing LLC. [http://dx.
doi:10.1063/1.3587245 pmid:21599062 fatcat:eh5jbizbdbd45lofyd6h4jjmhm