@entity3884 -transfer reactions are an important class of reactions in many chemical and biological processes. Barrier heights of @entity8108 -transfer reactions are underestimated significantly by popular exchange-correlation functional with density functional theory (DFT), while coupled-cluster (CC) method is quite expensive and can be applied only to rather small systems. Quantum Monte-Carlo method can usually provide reliable results for large systems. Performance of fixed-node diffusion quantum Monte-Carlo method (FN-DMC) on barrier heights of the 19 @entity8108 -transfer reactions in the HTBH38/08 database is investigated in this study with the trial wavefunctions of the single-Slater-Jastrow form and orbitals from DFT using local density approximation. Our results show that barrier heights of these reactions can be calculated rather accurately using FN-DMC and the mean absolute error is 1.0  kcal/mol in all-electron calculations. Introduction of pseudopotentials (PP) in FN-DMC calculations improves efficiency pronouncedly. According to our results, error of the employed PPs is smaller than that of the present CCSD(T) and FN-DMC calculations. FN- @entity33679 using PPs can thus be applied to investigate @entity8108 -transfer reactions involving larger molecules reliably. In addition, bond dissociation energies of the involved molecules using FN-DMC are in excellent agreement with reference values and they are even better than results of the employed CCSD(T) calculations using the aug-cc-pVQZ basis set.    2017 Wiley Periodicals, Inc.

Barrier heights of XXXX -transfer reactions with diffusion quantum monte carlo method.

@entity8108 :: ('D006859', 'Chemical') :: ['H'] @entity33679 :: ('MESH:C004944', 'Chemical') :: ['DMC'] @entity3884 :: ('MESH:D006859', 'Chemical') :: ['Hydrogen']
@entity3884 :: (MESH:D006859,Chemical) :: ['hydrogen']
