[23] C.M. Nelson, T.A. Moore, M. Okumura, T. K. Minton, J. Chem. Phys. 100 (1994) 8055.
[24] R.S. Mulliken, Phys. Rev. 61 (1942) 277.
[25] K. Kuwata, W.A. Goddard, M. Okumura, personal communication, referenced in C.M. Nelson, T.A. Moore and M. Okumura, J. Chem. Phys. 100 (1994) 8055.