Electronic and vibrational structures of corannulene anions

Electronic and vibrational structures of anionic corannulenes, C20H10-, C20 H102-, C20H103-, and C20H104-, are studied on the basis of the ab initio mo lecular orbital calculation at the HF/6-31G**, MP2/6-31G**//HF/6-31G**, and CASSCF/6-31G**//HF/6-31G** levels of theory. Analytical solutions of Hucke l Hamiltonian are also presented. The difference in,geometries and electron ic and vibrational structures among these corannulene anions, and the Jahn- Teller effect appearing in C20H10- and C20H103-, are discussed. The ground state of dianion is a singlet state. It is found that the wavenumbers of th e infrared-active C-PI stretching mode of corannulene anions decrease linea rly as corannulene become more negative. It can be used as the identificati on of the reduction stage of a corannulene anion. We also found that the Ja hn-Teller coupling of trianion is larger than that of monoanion.