Ground and Low-Lying Excited Electronic States of Difluorodiazirine

Autor:	Mark R. Hoffmann, Rajeev R. Pandey, Yuriy G. Khait
Rok vydání:	2004
Předmět:	Coupled cluster Excited electronic state Basis (linear algebra) Chemistry Physics::Atomic and Molecular Clusters Quadratic configuration interaction Molecule Perturbation theory (quantum mechanics) Physical and Theoretical Chemistry Atomic physics Ground state Excitation
Zdroj:	The Journal of Physical Chemistry A. 108:3119-3124
ISSN:	1520-5215 1089-5639
Popis:	Ground and low-lying excited electronic states of difluorodiazirine (F2CN2) were investigated using the recently revised, multireference, second-order generalized Van Vleck perturbation theory (GVVPT2). Initial studies on the ground state were carried out with the single-reference Moller−Plesset second order perturbation theory (MP2), quadratic configuration interaction with single and double excitation (QCISD), and coupled cluster with single, double, perturbative triple excitations (CCSD(T)) methods using several correlation-consistent atomic basis sets. MP2 and QCISD did not give semiquantitatively correct descriptions of the ground state of the molecule. For the ground state, GVVPT2 results are in close agreement with CCSD(T) but lie slightly closer to the experimental results. A balanced treatment of nondynamic and dynamic correlation effects has been shown to be of crucial importance for correct description of the system. Equilibrium geometries, excitation energies, and thermodynamic stabilities of ...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::36c6e5d96f6d824bc8af9d9ef1dd0118 https://doi.org/10.1021/jp0311658 Zobrazit plný text záznamu