title: Anharmonic frequencies of CX2Y2 (X, Y = O, N, F, H, D) isomers and related systems obtained from vibrational multiconfiguration self-consistent field theory.
abstract: Accurate anharmonic frequencies are provided for molecules of current research, i.e., diazirines, diazomethane, the corresponding fluorinated and deuterated compounds, their dioxygen analogs, and others. Vibrational-state energies were obtained from state-specific vibrational multiconfiguration self-consistent field theory (VMCSCF) based on multilevel potential energy surfaces (PES) generated from explicitly correlated coupled cluster, CCSD(T)-F12a, and double-hybrid density functional calculations, B2PLYP. To accelerate the vibrational structure calculations, a configuration selection scheme as well as a polynomial representation of the PES have been exploited. Because experimental data are scarce for these systems, many calculated frequencies of this study are predictions and may guide experiments to come.
authors: Institut für Theoretische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany.
authors: Florian
authors: F
authors: Pfeiffer
authors: Guntram
authors: G
authors: Rauhut
mesh_terms: D001389:Azirines / Q000737:chemistry*; D003978:Diazomethane / Q000737:chemistry*; D013237:Stereoisomerism; D014732:Vibration
chemical_list: D001389:Azirines; D003978:Diazomethane