Document Details Document Type : Article In Journal  Document Title : Electron pair density in the lowest 1Σ u + and 1Σ g + states of H 2 Electron pair density in the lowest 1Σ u + and 1Σ g + states of H 2   Subject : Chemistry  Document Language : English  Abstract : We demonstrate and advocate the use of observable quantities derived from the two-electron reduced density matrix - pair densities, conditional densities, and exchange-correlation holes - as signatures of the type of electron correlation in a chemical bond. The prototype cases of the lowest 1u+ and 1g+ states of H 2, which exhibit large variation in types of bonding, ranging from strongly ionic to covalent, are discussed. Both the excited 1g+ and 1u+ states have been interpreted as essentially consisting of (natural) orbital configurations with an inner electron in a contracted 1s g orbital and an outer electron in a diffuse (united atom type, Rydberg) orbital. We show that nevertheless totally different correlation behavior is encountered in various states when comparing them at a common internuclear distance. Also when following one state along the internuclear distance coordinate, strong variation in correlation behavior is observed, as expected. Switches between ionic to covalent character of a state occur till very large distances (40 bohrs for states approaching the 1s3 asymptotic limit, and 282 bohrs for states approaching the 1s4 limit).  ISSN : 0021-9606  Journal Name : Journal of Chemical Physics  Volume : 135  Issue Number : 7  Publishing Year : 1432 AH 2011 AD  Article Type : Article  Added Date : Tuesday, May 1, 2012  Researchers Researcher Name (Arabic) Researcher Name (English) Researcher Type Dr Grade Email Jian Wang Wang, Jian Researcher Doctorate jwang572@hotmail.com Kwang S Kim Kim, Kwang S Researcher Doctorate kim@postech.ac.kr Evert Jan Baerends Baerends, Evert Jan Researcher Doctorate e.j.baerends@vu.nl Files File Name Type Description  33071.pdf pdf Abstract Back To Researches Page