ASSIGNMENT OF THE LOWEST EXCITED-STATES OF C-70 AND EVIDENCE FOR FLUORESCENCE FROM THE S-2 STATE

Highly structured fluorescence, phosphorescence, and fluorescence-exci tation spectra of C-70 in neon matrixes are reported. Fluorescence fro m both S-1 and S-2 states is observed, and these are identified as bei ng of A(2)' and E-1' symmetry and have gas-phase energies estimated at 15 560 and 15 725 cm(-1), respectively. A third singlet state is iden tified in the excitation spectrum and is proposed to be of A(2)'' symm etry with an estimated gas-phase energy of 16 000 cm(-1). Finally, the phosphorescence is dominated by vibrational bands of e(1)' symmetry p ointing to the lowest triplet state of A(2)' symmetry. Its energy lies at 12 588 cm(-1) above that of the ground state in the neon matrix. F rom a comparison with data from the literature, the existence of a sec ond triplet state of E-1' character is inferred, which lies about 165 cm(-1) above the lowest triplet state, i.e., with the same energy sepa ration as the lowest two singlet states.