A global potential energy surface for H₂S⁺(X ⁴A′′) and quasi-classical trajectory study of the S⁺(⁴S) + H₂(X¹Σ⁺_g) reaction

ABSTRACT

A novel global potential energy surface for H₂S⁺(X ⁴A″) based on accurate ab initio calculations is presented. Energies are calculated at the multi-reference configuration interaction level with Davidson correction using aug-cc-pVQZ basis set plus core-polarisation high-exponent d functions. A grid of 4552 points is used for the least-square fitting procedure in the frame of a many-body expansion. The topographical features of the new potential energy surface are here discussed in detail. Such a surface is then employed for dynamic studies of the S(⁴S) + H₂(X ¹Σ⁺_g) →SH⁺(X ³Σ⁻) + H(²S) reaction using the quasi-classical trajectory method. State specific trajectories are calculated, for both ground and ro-vibrationally excited initial states of H₂(X ¹Σ⁺_g). Corrections to the zero point energy leakage of the classical calculations are also presented. Calculated reaction cross sections and rate constants are here reported and compared with available literature.

KEYWORDS:

• Potential energy surface
• molecular dynamics
• classical trajectories

Acknowledgments

Financial Support from China Postdoctoral Science Foundation [grant number 2014M561957]; National Natural Science Foundation of China [grant number 11304185]; Natural Science Foundation of Shandong Province [grant number ZR2014AM022]; Shandong Province Higher Educational Science and Technology Program [grant number J15LJ03]; Post-Doctoral Innovation Project of Shandong Province [grant number 201402013] and FAPEMIG, Brazil is acknowledged.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

China Postdoctoral Science Foundation [grant number 2014M561957]; National Natural Science Foundation of China [grant number 11304185]; Natural Science Foundation of Shandong Province [grant number ZR2014AM022]; Shandong Province Higher Educational Science and Technology Program [grant number J15LJ03]; Post-Doctoral Innovation Project of Shandong Province [grant number 201402013].