THE NEGLECT OF BASIS-SET SUPERPOSITION ERROR IN THE ACCURATE THEORETICAL DETERMINATION OF HEATS OF FORMATION

We investigate the effect of neglecting the basis set superposition error in the theoretical determination of DELTAH(f). We show that this error is, in fact, larger than the claimed accuracy of recent computations of theoretical heats of formation. We further demonstrate that neglecting the basis set superposition error correction can lead to improved agreement between experimental values and those obtained theoretically using small to moderate sized basis sets. In light of the size of this error, however, some caution should be used when assessing the accuracy of a theoretical method in which the basis set superposition error is neglected.