High-accuracy extrapolated ab initio thermochemistry of vinyl chloride.

Applying a modified "high accuracy extrapolated ab initio thermochemistry" (HEAT) scheme, the standard heat of formation of vinyl chloride at 0 K is computed to be 29.79 +/- 1 kJ/mol and at 298.15 K to be 20.9 +/- 2 kJ/mol, thus resolving earlier discrepancies among the available experimental values, which span a range from 21 up to 38 kJ/mol. The enthalpies of the reactions C2H4 + Cl2 --> CH2CHCl + HCl and C2H2 + HCl --> CH2CHCl at 298.15 K are determined to be -123.0 and -113.9 +/- 2 kJ/mol, respectively.