Cw. Bauschlicher et al., Boron heat of formation revisited: Relativistic effects on the BF3 atomization energy, J PHYS CH A, 103(38), 1999, pp. 7715-7718
The one-electron Douglas-Kroll approach, and perturbation theory including
only the mass-velocity and Darwin terms, are used to compute the scalar rel
ativistic contribution to the atomization energies of BS. Both approaches p
redict an approximately 0.7 kcal/mol reduction in the atomization energy. I
n combination with improved one-particle extrapolation techniques, this lea
ds to a revised estimate for the heat of formation of gaseous boron, Delta
H(f,0)degrees[B(g)] = 135.1 kcal/mol and Delta H(f,298)degrees[B(g)] = 136.
3 kcal/mol, with error bars +/-0.75 kcal/mol or less.