Equilibrium Structure and Spectroscopic Constants of Dichloroethyne: An ab Initio Study

High-level ab initio calculations with large basis sets are reported for dichloroethyne, ClCCCl. Based on CCSD(T)/cc-pVQZ results, an empirically corrected theoretical equilibrium geometry is derived: re(CC) = 1.2025(6) A and re(CCl) = 1.635(5) A. Correlated harmonic (CCSD(T)/cc-pVQZ) and anharmonic (MP2/TZ2Pf) force fields provide theoretical predictions for the fundamental vibrational wavenumbers and many other spectroscopic constants for the four most important isotopomers of dichloroethyne. Copyright 1997 Academic Press. Copyright 1997Academic Press