Theoretical calculation of the heat of formation of fulvene

The experimental value for the heat of formation of fulvene is 53.6 or 53.5 kcal mol−1 depending on the source. However, no theoretical calculation seems to reproduce that value. In this work, we deduce the heat of formation of fulvene from high-level ab initio calculations. The analysis of our results compared to similar theoretical calculations and experiments data leads to suggest a heat of formation of 51.17 ± 0.37 kcal mol−1, which remains lower than the experimental value.