Intermolecular interaction from biorthogonal orbitals: new developments

Abstract

New developments to compute the intermolecular interaction between two subsystems are proposed. They are based on biorthogonal orbitals and second quantization techniques. Test calculations have been performed on some geometrical configurations of a water dimer and on the strongly H-bonded OH⁻(H₂O) system. All second-order intermolecular and mixed (inter–intra) terms are included. The results are compared with previously published SAPT calculations and with MP2 supermolecule treatment. They are all generally in good agreement. However, the description of the repulsive wall is sensitive to the quality of the basis set. The choice of a suitable basis set for the strongly H-bonded system is especially delicate.

Acknowledgements

The calculations were performed in Strasbourg using our laboratory work stations. The CNRS and the University Louis Pasteur de Strasbourg are acknowledged for providing computer facilities. Dr. Lilyane Padel and Mrs Sylvie Fersing are thanked for their help and technical assistance.

Notes

Present address: Department of Chemistry, Norwegian University of Science and Technology, 7491 Trondheim, Norway.

Additional information

Notes on contributors

Jean-François Gouyet

Present address: Department of Chemistry, Norwegian University of Science and Technology, 7491 Trondheim, Norway.