Search results for "Polyatomic molecule"
showing 3 items of 3 documents
Selected dissociation‐ and correlation‐consistent configuration interaction by a perturbative criterion
1990
We propose a perturbative criterion to select the most important dissociation‐ or correlation‐consistent type of contributions to perform generalized valence bond‐configuration interaction (GVB‐CI) calculations, dissociation‐consistent configuration interaction (DCCI) or correlation‐consistent configuration interaction (CCCI) approach, respectively. The procedure presented is computationally less demanding than the CCCI proposed by Goddard and co‐workers. To ensure the distance consistency of the MOs used, the nonvalence virtual orbitals are obtained by a projection technique. The results obtained for a few test calculations show the ability of the suggested approach to get close results to…
On the semi-empirical determination of intramolecular potential energy surface of polyatomic molecule: application to hydrogen sulfide, hydrogen sele…
2007
The Controversy Between Erich Hückel and Linus Pauling over the Benzene Problem
2009
Shortly after Huckel’s quantum-theoretical work on the problem of aromatic compounds was published, the first paper on the same subject by the American Linus Pauling also appeared. It was the fifth installment of a total of seven that Pauling published between April 1931 and July 1933 under the general title The Nature of the Chemical Bond.This fifth part was the first coauthored with his pupil George Wheland, a National Research Fellow in Pasadena. In their quantum mechanical treatment of benzene, naphthaline and free organic radicals, they applied a “VB” approximation slightly different from Huckel’s “first method” yet sharing some resemblance with it. The two subsequent parts of Pauling’…