Structure and bonding of H2O2•••X complexes with (X = NO+, CN-, HCN, HNC, CO)

Accurate B3LYP and MP2 theoretical calculations, with the 6-311+G(3df,2p) basis set, have been performed on different complexes, between hydrogen peroxide (HP) and NO+ (1), CN- (2-4), HCN (5-8), HNC (9-12) and CO (13 and 14). According to the binding energy obtained, the charged complexes (1-4) have large binding-energy values, yielding only cyclic stationary points. However, the neutral complexes (5-14) showed medium to small binding-energy values with linear and cyclic arrangements, the cyclic structures being transition states and the linear complexes minima, on their corresponding PESs. The "atoms in molecules'' theory (AIM) was used to characterize the intermolecular interactions, ranging from electrostatic interactions for the HP ... NO+ complex (1) to different types of hydrogen bonding for 2 to 14. For all the structures, the binding energy was corrected for the BSSE by the counterpoise (CP) method. Moreover, calculations were performed also on the BSSE-corrected PESs.