THEORETICAL-STUDY OF THE C-H BOND-DISSOCIATION ENERGY OF C2H

We present a theoretical study of the convergence of the CH bond dissociation energy (DO) in C2H with respect to both the one- and n-particle spaces. The calculated CH bond energies of C2H2 and C2H4, which are in excellent agreement with experiment, are used for calibration. Our best estimate for DO of 112.4 ± 2.0 kcal/mol is slightly below the recent experimental value of 116.3 ± 2.6 kcal/mol, but substantially above a previous theoretical estimate of 102 kcal/mol. The remaining discrepancy with experiment may reflect primarily the uncertainty in the experimental DO value of C2 required in the analysis. © 1990.