Premium
Construction and applications of symmetrized valence bond wave functions
Author(s) -
Cao Zexing,
Wu Wei,
Zhang Qianer
Publication year - 1998
Publication title -
international journal of quantum chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.484
H-Index - 105
eISSN - 1097-461X
pISSN - 0020-7608
DOI - 10.1002/(sici)1097-461x(1998)66:1<1::aid-qua1>3.0.co;2-z
Subject(s) - excited state , wave function , chemistry , singlet state , valence (chemistry) , valence bond theory , ground state , dipole , generalized valence bond , excitation , atomic physics , bond length , coupled cluster , molecule , bond order , physics , quantum mechanics , molecular orbital , organic chemistry
A method constructing symmetry‐adapted bonded Young tableau bases is proposed, based on the symmetry properties of bonded tableaus and the projection operator associated with a point group. Several examples including the ground states and π excited states of O 3 − , O 3 , O 3 + , and C 3 − are shown for instruction to construct the symmetrized valence bond (VB) wave function. Excitation energies of transitions from the ground states to π excited states of O 3 − , C 3 H 5 , and C 3 − are calculated with an optimized symmetrized valence bond wave function in the σ–π separation approximation. Good agreement between the VB and experimental excitation energies is observed. The bonding features of the ground state and the first π excited singlet and triplet states for S 3 are discussed according to bonding populations from VB calculations. Both the singlet‐biradical and the dipole structures have significant contributions to the ground state X 1 A 1 of S 3 , while the excited state 1 1 B 2 is essentially composed of the dipole structures, and the 1 3 B 2 excited state is comprised from a triplet‐biradical structure. © 1998 John Wiley & Sons, Inc. Int J Quant Chem 66 : 1–7, 1998