Comparison between standard and counterpoise-corrected optimization using some hydrogen and halogen bonded systems

Abstract

The effect of the counterpoise correction on the geometries, stabilization energies, and vibrational harmonic frequencies of some hydrogen-and halogen-bonded systems ) has been analysed at the MP2 level of theory using the popular 6-311þþG(d,p) basis set. The optimized B Á Á Á H and B Á Á Á X bond lengths increase with counterpoise (CP) correction. In some cases standard values and in other cases CP-corrected values are close to experimental data. The absolute values of complexation energies of CP-corrected structures are higher than standard by inclusion of BSSE correction. The effect of CP correction on intermolecular bond lengths and complexation energies of B Á Á Á XY series are usually higher than B Á Á Á HX. Also, this effect is higher for H 2 S and PH 3 groups. The CP correction changes the vibrational harmonic frequencies by 0-100%. The changes are frequently lower than 20% for frequencies higher than 300 cm À1 .

Cooperativity between the Halogen Bond and the Hydrogen Bond in H3N⋅⋅⋅XY⋅⋅⋅HF Complexes (X, Y=F, Cl, Br)

“…The MP2/6-311 + + GA C H T U N G T R E N N U N G (d,p) method has been used for the complexes H 3 N···Br 2, H 3 N···Cl 2 , H 3 N···ClF, H 3 N···BrF, H 3 N···BrCl. [23] Interaction energies DE were calculated by subtracting the energy sum of all monomers from the energy of the complex. The interaction energies of the complexes were corrected for basis set superposition error (BSSE) by using the counterpoise correction method.…”

Halogen Bonding Involving CO and CS with Carbon as the Electron Donor

“…These include an early investigation of charge transfer in complexes involving dihalogen compounds and CO [ 25 ], and a study of the competition between halogen bonds and hydrogen bonds in 1:1 complexes involving CO and hypohalous acids [ 26 ]. Studies of the complexes formed between CO and dimers and trimers of dihalogen molecules XY, for X, Y = Cl, Br, have been published [ 27 , 28 ], as well as a study of the difference between standard and counterpoise-corrected optimized geometries of halogen- and hydrogen-bonded complexes [ 29 ]. A recent conference on Halogen Bonding highlighted both experimental and theoretical studies of this important intermolecular interaction [ 30 ].…”