Six-dimensional quantum calculation of the intermolecular bound states for water dimer

• Published in: The Journal of chemical physics 1999-01, Vol.110 (1), p.168-176
• Main Authors: Chen, Hua, Liu, S., Light, J. C.
• Format: Article
• Language: English
• ISSN: 0021-9606; 1089-7690
• DOI: 10.1063/1.478092

We present results of six-dimensional bound-state calculations of the vibrations of rigid water dimer based on two older and two very recent potential energy surfaces. The calculations are done by a new sequential diagonalization–truncation approach using the symmetrized angular basis presented most recently by Althorpe and Clary [J. Chem. Phys. 101, 3603 (1994)] and a potential optimized discrete variable representation (DVR) in the monomer–monomer distance coordinate. The lowest ten or so states of each symmetry are apparently converged to 0.5 cm−1 using a coupled angular basis of Wigner rotation functions with Jmax=11 and mmax=5 on each monomer. The results differ significantly from the results presented by Leforestier et al. [J. Chem. Phys. 106, 8527 (1997)] and demonstrate that the ASP-S potential yields more accurate tunneling splittings than the more recent ASP-Wx potentials [C. Millot et al., J. Phys. Chem. A 102, 754 (1998)].