Application of the Pariser-Parr-Pople method to the croconate ion (C5O 5 −2 )

Parr, R. G.: Quantum theory of electronic structure. New York: W. A. Benjamin Publisher 1962. Ladik, J., andK. Appel: Preprint no. 79; June 1, 1962, Quantum Chemistry Group; Uppsala University, Sweden. Nishimoto, K., andL. S. Forster: Theoret. chim. Acta3, 407 (1965). Baezinger, N. C., andJ. J. Hegenbarth: J. Amer. chem. Soc.86, 3250 (1964). Hinze, J., andH. H. Jaffé: J. Amer. chem. Soc.84, 540 (1962). Maya, Y.: Preprint B110 of the international symposium on molecular structure and spectroscopy, Tokyo, Sept. 1962. Roothaan, C. C. J.: J. chem. Physics19, 1445 (1951). Orloff, M. K., andO. Sinanoglu: J. chem. Physics43, 49 (1965). Julg, A.: J. Chim. physique57, 19 (1960).Anno, T., I. Sadò, andA. Matabura: Bull. chem. Soc. Japan30, 168 (1957). Stewart, E. T.: J. chem. Soc. [London]1959 70, 1856. Cignitti, M., andL. Paoloni: Gazz. chim. ital., in press.Moffat, J. B.: Canad. J. Chem.42, 1323 (1964). Niseimoto, K., andN. Mataga: Z. physik. Chem. [Frankfurt]12, 335;13, 140 (1957). West, R., andH. Y. Niu: J. Amer. chem. Soc.85, 2586 (1963). —, andD. L. Powell: J. Amer. chem. Soc.85, 2577 (1963). Kon, I.: Bull. chew. Soc. Japan28, 275 (1955). Yamada, K., N. Mizuno, andY. Hirata: Bull. chem. Soc. Japan31, 543 (1958).Carlqvist, B., andD. Dyrssen: Acta chem. scand.16, 94 (1962). Bratoz, S., andS. Besnainou: J. chem. Physics34, 1142 (1962). Liehr, A. D.: Z. physik. Chem. [Frankfurt]9, 338 (1956). Ito, M., andR. West: J. Amer. chem. Soc.85, 2580 (1963).