The microwave spectrum, harmonic force field, and structure of difluorodichloromethane

CASPT2 study on electronic states of the dichlorodifluoromethane cation

“…The CASPT2 calculations for the ground state (1 1 A 1 ) of the CF 2 Cl 2 molecule were performed based on the CASSCF (16,12) calculations, and the CASPT2 optimized geometry for the molecule is in reasonable agreement with the experimental geometry [16] (see the last two lines of Table 2). In the following we will compare the CASPT2 geometries of the ionic states with the CASPT2 geometry of the ground-state molecule.…”

“…The CASSCF geometry optimization and frequency calculations were performed for the eight states of the CF 2 Cl þ 2 ion, and the geometries were refined in the CASPT2 geometry optimization calculations (at the present stage it is not possible for us to perform the CASPT2 frequency calculations). On the basis of the CASPT2 energy calculations at the CASPT2 and CASSCF optimized geometries, we [16] of the ground-state molecule, we obtained the CASPT2 relative energies (denoted as CASPT2 T 0 v ) of the excited states to the 1 2 B 2 ground state at the molecular geometry.…”

“…b Ref. [16]. these seven states are the primary ionization states (''hole states'') at the geometry of the molecule.…”

The Limits of Rovibrational Analysis: The Severely Entangled ν1 Polyad Vibration of Dichlorodifluoromethane in the Greenhouse IR Window

“…Table 2. Experimentally Determined Gas Phase Fundamental Band Positions for C 35 Cl 2 F 2 , and Isotopic Shifts for 37 Cl-and 13 C-Substituted Species (in cm IR spectra. High-resolution room-temperature spectra were obtained using R12 (Sigma-Aldrich, >99% purity) in a standard White cell with path length set to 6.6 m. A cooling cell 30 fitted with KBr or CaF 2 windows and with optical path set to 2.5 m was used to measure low-temperature spectra.…”

“…A number of investigations have focused on the quantitative aspects, measuring integrated band strengths of R12 within the atmospheric window (e.g., refs 12−15). High-resolution investigations have been conducted for the ν 6 band of C 35 Cl 2 F 2 , 16,17 C 35 Cl 37 ClF 2 , 17,18 and C 37 Cl 2 F 2 . 19 D'Amico et al 20 subsequently studied the ν 3 + ν 7 combination at ≈ 888 cm −1 , the fourth strongest band in the IR atmospheric window, with its considerable intensity stolen from ν 6 via a Fermi resonance.…”