Energy-switching potential energy surface for the water molecule revisited: A highly accurate singled-sheeted form.
A global ab initio potential energy surface is proposed for the water molecule by energy-switching/merging a highly accurate isotope-dependent local potential function reported by Polyansky et al. [Science 299, 539 (2003)] with a global form of the many-body expansion type suitably adapted to account explicitly for the dynamical correlation and parametrized from extensive accurate multireference configuration interaction energies extrapolated to the complete basis set limit. The new function mimics also the complicated Sigma/Pi crossing that arises at linear geometries of the water molecule.
Galvão
B R L
BR
Departamento de Quimica, Universidade de Coimbra, 3004-535 Coimbra, Portugal.
Rodrigues
S P J
SP
Varandas
A J C
AJ