1. Karplus, M., Porter, R. N., and Sharma, R. D.: 1965, J. Chem. Phys. 43, 3259.
2. Christov, S. G.: 1972, Berichte Bunsen-Gesellschaft fur Physikalische Chemie
76, 507.
3. Eyring, H., Walter, J., and Kimbal, G. E.: 1946, Quantum Chemistry, Wiley.
4. For details see ‘Potential Energy Surface in Chemistry’, IBM Research Laboratory (1970).
5. Dedieu, A. and Veillard, A.: J. Am. Chem. Soc., in press.