Negative ion photoelectron spectroscopy of 2,2'-bithiophene cluster anions, (2T)n- (n = 1–100) M. Mitsui, Y. Matsumoto, N. Ando and A. Nakajima Eur. Phys. J. D, 34 1-3 (2005) 169-172 Published online: 13 July 2005 DOI: 10.1140/epjd/e2005-00139-0