Correlation Energy of Ethylene and Acetylene

Abstract

A series of self‐consistent‐field calculations are reported for the molecules C₂, ethylene, and acetylene in a Gaussian basis. An upper limit for the correlation energy of ethylene and acetylene of 0.645 and 0.597 a.u. has been computed. The correlation energy is estimated to be too high by 0.045 to 0.084 a.u. based on the results of the C₂ calculation.