Q. Excited and ionized states of ethylene
A. For the valence excited states and ionized states, a recommended
basis sets is the triple-zeta and polarization d-function for the C atoms, and
the double-zeta and polarization p-function for the H atoms. These basis sets
are augmented with Rydberg s and p set on carbons and
two diffuse d-functions on the center of the bond.
For calculating Rydberg states, at least
additional s and p type Rydberg functions should be
included. See test634 and its description in the Part-I-L of the SAC-CI guide.
See also previous articles
H. Nakatsuji, J. Chem. Phys. 80 (1984) 3703.
C.C. Ballard, M. Hada, and H.
Nakatsuji, Bull. Chem. Soc. Jpn. 69 (1996) 1901.
J. Hasegawa, M. Ehara, and H. Nakatsuji, Chem. Phys. 230 (1998) 23.