Dissociation energy of the molecule GeCl

Mass spectrometry was used to identify the gaseous species GeCl, CuCl, Ge, and Cu in a molecular beam issuing from an effusive source, and to evaluate the equilibrium constant for the monochloride exchange reaction in the range 1543–1776 K. From the derived reaction enthalpy, the dissociation energy, D0o, of GeCl was evaluated as 92.5 ± 2.3 kcal mol−1. The thermochemical value is lower than a spectroscopic value derived from a short extrapolation of vibrational levels in the 4Σ− state, indicating a potential maximum of about 7 kcal mol−1 in that state.