A multiconfiguration self-consistent-field (MCSCF) study of the bent and linear conformations of HCCN
- 15 June 1987
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 86 (12) , 7051-7053
- https://doi.org/10.1063/1.452354
Abstract
An MCSCF procedure of the complete active space (CAS) genre has been used to predict the structures and energetics of the HCCN molecule. Full configuration interaction (CI) within the π‐electron space (1π x , 1π y , 2π x , 2π y , 3π x , 3π y orbitals, six electrons) was used in these MCSCF studies. With double zeta plus polarization (DZP) and triple zeta plus double polarization (TZ2P) basis sets, the bent structure lies 6.2 and 5.7 kcal, respectively, below the linear conformation. Multireference CI wave functions reduce this energy difference significantly.Keywords
This publication has 13 references indexed in Scilit:
- A second order multiconfiguration SCF procedure with optimum convergenceThe Journal of Chemical Physics, 1985
- Structure and harmonic vibrational frequencies of the carbon suboxide molecule using analytic derivative methodsChemical Physics Letters, 1984
- The microwave spectrum of a triplet carbene: HCCN in the X 3Σ− stateThe Journal of Chemical Physics, 1984
- Vibrational frequencies of the cyanocarbene (HCCN) molecule. A near degeneracy between bent cyanocarbene and linear allene-related geometriesJournal of the American Chemical Society, 1983
- A complete active space SCF method (CASSCF) using a density matrix formulated super-CI approachChemical Physics, 1980
- Matrix isolation spectroscopic study of the free radical HCCNThe Journal of Chemical Physics, 1977
- EPR of CH2: a substiantially bent and partially rotating ground state tripletChemical Physics Letters, 1970
- Gaussian-Type Functions for Polyatomic Systems. IThe Journal of Chemical Physics, 1965
- Paramagnetic Resonance of Triplet CyanomethyleneThe Journal of Chemical Physics, 1964
- Self-Consistent Field Theory for Open Shells of Electronic SystemsReviews of Modern Physics, 1960