P. Duffy et Dp. Chong, STUDY OF TRANSITION-STATE METHODS IN THE CALCULATION OF VERTICAL IONIZATION-POTENTIALS BY LOCAL-DENSITY APPROXIMATION, Organic mass spectrometry, 28(4), 1993, pp. 321-326
The vertical ionization potentials of nine small molecules were comput
ed by the deMon density functional program and different versions of t
he transition-state method and the results were compared with earlier
calculations and with experiment. The average absolute deviation of th
e 38 computed ionization potentials of the valence electrons of nine s
mall molecules from experiment is 0.4 eV, which compares well with pre
vious ab initio post-Hartree-Fock and semi-empirical HAM/3 calculation
s. The efficient methods were then used to calculate 68 ionization pot
entials of sixteen 22-electron molecules, with results of similar qual
ity.