title: Study of the Vibrational Spectra and Absorption Cross Sections of 1-Chloro-1-fluoroethene by a Joint Experimental and Ab Initio Approach.
abstract: The gas-phase infrared spectra of 1-chloro-1-fluoroethene (geminal chloro-fluoroethene, ClFC═CH2, 1,1-C2H2ClF) were recorded at medium resolution in the range of 400-6400 cm-1, and the vibrational analysis led to revised assignments for the ν11(A″ symmetry), ν2(A' symmetry), and ν1(A' symmetry) bands. Besides the fundamentals, all the most important spectral features were interpreted in terms of overtone and combination bands, thus obtaining an accurate description of the vibrational structure of ClFC═CH2. Accurate measurements of absorption cross-sectional spectra were carried out, and integrated band intensity data were determined. High-level ab initio calculations of harmonic and anharmonic force fields thoroughly supported and guided the analysis and the disentangling of the several strongly coupled polyads involving many vibrational levels. Diagonalization of the effective Hamiltonian with the off-diagonal elements involving several Fermi and Darling-Dennison resonance coefficients computed by the theoretical cubic and quartic force constants provided the predicted energy levels in good agreement with the vibrational assignments. The calculated infrared intensities, obtained by taking into account anharmonic corrections, were compared to the accurate experimental absorption cross-sectional data determined here.
authors.affiliation: Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca' Foscari Venezia , Via Torino 155, 30172 Mestre (Ve), Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Pietropolli Charmet
authors.affiliation: Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca' Foscari Venezia , Via Torino 155, 30172 Mestre (Ve), Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Stoppa
authors.affiliation: Scuola Normale Superiore , Piazza dei Cavalieri 7, 56126 Pisa (Pi), Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Tasinato
authors.affiliation: Dipartimento di Scienze Molecolari e Nanosistemi, Università Ca' Foscari Venezia , Via Torino 155, 30172 Mestre (Ve), Italy.
authors.forename: Santi
authors.initials: S
authors.lastname: Giorgianni
authors.affiliation: Dipartimento Politecnico di Ingegneria e Architettura, Università degli Studi di Udine , Via Cotonificio, 108, 33100 Udine (Ud), Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Gambi