Ornstein-Uhlenbeck diffusion quantum Monte Carlo study on the bond lengths and harmonic frequencies of some first-row diatomic molecules

Department of Applied Chemistry, Fooyin University, 151 Chinhsueh Road, Ta-Liao Hsiang, Kaohsiung Hsien, 831 Taiwan.
The Journal of Chemical Physics (Impact Factor: 2.95). 03/2004; 120(7):3185-8. DOI: 10.1063/1.1639370
Source: PubMed


This article accesses the performance of the Ornstein-Uhlenbeck diffusion quantum Monte Carlo with regard to the calculation of molecular geometries and harmonic frequencies of H2, LiH, HF, Li2, LiF, CO, N2, and F2 molecules. A comparison of the results for the eight first-row diatomic molecules from experiments, CCSD(T)/6-311G(3df,3pd) and CCSD(T)/cc-pV5Z levels of theory as well as our work is given. The results presented show that quantum Monte Carlo is becoming powerful tools for ab initio electronic structure calculations.

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