Inclusion of exact exchange for self - interaction corrected H 3 density functional potential energy surface Gabor

The e€ect of the inclusion of the exact exchange into self-interaction corrected generalized gradient approximation density functional theory (GGA-DFT) for the simplest hydrogen abstraction reaction, H + H 2 ® H 3 ® H 2 + H, is presented using a triple-zeta augmented 6-311++G(d,3pd) basis set. The introduction of the self-interaction correction has a considerably larger e€ect on molecular geometry and vibrational frequencies than the inclusion of the exact exchange. We investigate the in¯uence of the self-interaction error on the shape of the potential energy surface around the transition state of the hydrogen abstraction reaction. The decomposition of the self-interaction error into correlation and exchange parts shows that the exchange self-interaction error is the main component of the energy barrier error. The best agreements with the experimental barrier height were achieved by self-interaction corrected B3LYP, B-LYP and B3PW functionals with errors of 1.5, 2.9 and 3.0 kcal/mol, respectively. Self-interaction components ± B3LYP and B3PW func-tionals ± Self-interaction corrected molecular geometries ± Self-interaction corrected total energies