Abstract

The basis-set dependence and quasirelativistic and nonrelativistic effects on the Au - C2H4 interaction are examined at the ab initio level. The effects on the interaction energies are modulated by f-type polarization orbitals, using 19-VE quasirelativistic pseudopotentials. Oscillation in the equilibrium Au - C distance as well as in the interaction energy are sensitive to the electron correlation potential. These effects are evaluated at several levels of theory, ranging from MP2 to CCSD(T). The nature of the Au - C2H4 interaction is related to a simple dispersion expression involving the individual properties of each component and its long-distance behavior. © 1999 John Wiley & Sons, Inc.