Abstract
The role of spin contamination and quasidegeneracy in the energetics of a simple hydrogen abstraction reaction is studied by applying recently developed coupled-cluster (CC) methods to an exactly solvable model for the F+H2→HF+H reaction [C. W. Bauschlicher and P. R. Taylor, J. Chem. Phys. 86, 858 (1987)]. To assess the role of spin contamination, the (spin)-unrestricted Hartree–Fock (UHF) CC with singles and doubles (CCSD) barrier height is compared with that obtained with a fully spin-adapted unitary group approach (UGA) based CCSD, while the quasidegeneracy effects are examined using the so-called reduced multireference (RMR) CCSD method. It is shown that the effect of spin contamination on the barrier height is more significant (0.7 kcal/mol) than that of the quasidegeneracy (0.2 kcal/mol), although the latter plays a more significant role for exothermicity. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 77: 281–290, 2000
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
