TY - BOOK AU - Del Re,Giuseppe,1932- AU - Berthier,Gaston,1923- AU - Serre,Josiane,1922- TI - Electronic states of molecules and atom clusters: foundations and prospects of semiempirical methods T2 - Lecture notes in chemistry SN - 0387097384 PY - 1980/// CY - Berlin PB - Springer-Verlag KW - Molecular theory N1 - Bibliography: p. 160-177 ER -