Journal of Chemical Physics, Vol.115, No.22, 10146-10153, 2001
Superfluid solvation structure of OCS in helium clusters
We make a detailed study of the local solvation structure and energetics of an OCS molecule in clusters of He-4 at finite temperatures. Calculations are made with the path integral Monte Carlo method, incorporating the exchange permutation symmetry of the bosonic He-4 atoms. Analysis of the local extent of superfluidity is made with an approximate exchange path estimator developed previously. The sensitivity of the helium solvation structure to the interaction potential is examined with calculations for two recently published He-OCS potentials, and the vibrational shift of the antisymmetric OCS vibration is estimated from a set of vibrationally adiabatic potentials. We comment on possible effects of molecular rotation on the local solvation structure, and discuss the microscopic two-fluid analysis of the rotational spectroscopy of OCS in He-4(N).