Basic ideas for the correction of semiempirical methods describing H-bonded systems

Abstract In this Letter, we show how semiempirical methods may be improved to describe hydrogen-bonded systems and proton transfer reactions. The approach consists in a redefinition of the core–core interaction terms that, as previously shown, are at the origin of spurious artifacts in standard methods. The parameterization of the new core–core functions is done using ab initio data of the intermolecular potential energy surfaces (PESs), which permits reaching the correct behavior at short and long interatomic distances. Here we report the parameters for O–O, O–H and H–H interactions. Extension to other atom pairs seems feasible, so the development of a semiempirical method adapted to the study of intermolecular interactions might be envisaged.

[1]  Simone Morpurgo,et al.  Critical test of PM3-calculated proton transfer activation energies: a comparison with ab initio and AM1 calculations , 1998 .

[2]  Gábor I. Csonka,et al.  Analysis of the core‐repulsion functions used in AM1 and PM3 semiempirical calculations: Conformational analysis of ring systems , 1993, J. Comput. Chem..

[3]  J. Dannenberg.  Hydrogen bonds: a comparison of semiempirical and ab initio treatments , 1997 .

[4]  Eamonn F. Healy,et al.  Development and use of quantum mechanical molecular models. 76. AM1: a new general purpose quantum mechanical molecular model , 1985 .

[5]  George C. Shields,et al.  Ability of the PM3 quantum‐mechanical method to model intermolecular hydrogen bonding between neutral molecules , 1993, J. Comput. Chem..

[6]  M. Bowers.  Gas phase ion chemistry , 1979 .

[7]  Harry Partridge,et al.  The determination of an accurate isotope dependent potential energy surface for water from extensive ab initio calculations and experimental data , 1997 .

[8]  H. Schaefer,et al.  The protonated water dimer: Extensive theoretical studies of H5O+2 , 1994 .

[9]  M. Meot-ner,et al.  Filling of solvent shells about ions. 1. Thermochemical criteria and the effects of isomeric clusters , 1986 .

[10]  János G. Ángyán,et al.  The origin of the problems with the PM3 core repulsion function , 1997 .

[11]  J. Stewart.  Optimization of parameters for semiempirical methods II. Applications , 1989 .

[12]  E. Coitiño,et al.  Theoretical studies of hydrogen-bonded complexes using semiempirical methods , 1990 .

[13]  Claude Millot,et al.  Improving description of hydrogen bonds at the semiempirical level: water–water interactions as test case , 2000 .

[14]  Oscar N. Ventura,et al.  Comparative ab initio and semi-empirical study of hydrogen bonded complexes of NH3 and H2O , 1992 .