Fourier Transform Infrared Spectra of CH2DF: The ν5 and ν6 Bands

The molecular potential energy surface and vibrational energy levels of methyl fluoride. Part II

“…The only change to the KEO from that of eqn (11) is the addition of terms involving second order derivative operators coupling the radial vectors to one other. 53 This change to the KEO and the use of a bond length V matrix (see eqn (8) of Part I 41 ) are the only alterations that need be made to the computer code. This allows the stretching ab initio PES to be tested in a variational calculation with the same coordinates.…”

“…Methyl fluoride is a very important prototype for experimental and theoretical studies in spectroscopy, [1][2][3][4][5][6][7][8][9][10] structure and bonding, [11][12][13][14][15][16][17] intramolecular dynamics 3,4,6,[17][18][19][20] and reaction dynamics. 17,[21][22][23] The spectroscopy and dynamics of a five-atom molecule such as methyl fluoride present a number of major challenges to both theory and experiment.…”

High resolution IR spectrum of the ν8 band of CH2DF: analysis of the interactions with the near vibrational levels

“…The ν 8 mode, described as CD out-plane-bend / CH 2 rock [5], is of A″ symmetry species and gives rise to a c-type band of medium intensity centred at 1298.58 cm -1 . The low resolution infrared spectrum of this band, depicted in Figure 1, shows the R branch partially overlapped by the P branch of the weaker ν 4 at 1364.17 cm -1 .…”

“…Low resolution IR analysis, aimed at the identification of the fundamental bands, was carried out long time ago [4]. In the first high resolution paper [5] the ν 5 and ν 6 fundamentals were analyzed as isolated bands, by fixing the ground state constants to the microwave values obtained by Clark and De Lucia [6].…”