dc.creator Lovas, F. J. en_US dc.creator Suenram, R. D. en_US dc.creator Kawashima, Y. en_US dc.creator Hirota, Eizi en_US dc.creator Biermann, S. en_US dc.creator Hoeft, J. en_US dc.creator Mawhorter, R. en_US dc.creator Törring, T. en_US dc.date.accessioned 2007-11-20T17:08:08Z dc.date.available 2007-11-20T17:08:08Z dc.date.issued 1995 en_US dc.identifier 1995-RD-06 en_US dc.identifier.uri http://hdl.handle.net/1811/29609 dc.description 1. R.C. Cave and I. OnO, J. Chem. Phys. 99, 9764 (1993). en_US dc.description Author Institution: National Institute of Standards and Technology, Gaithersburg, MD 20899.; Kanagawa Institute of Technology, Kanagawa, Japan; The Graduate University of Advanced Studies, Yokohama 227, Japan.; Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany.; Pomona College, 610 N. College Ave., Claremont, CA en_US dc.description.abstract The structures of alkali halide dimers have been predicted from numerous calculations ranging from ionic models to ab initi calculations. For symmetrical dimers electron diffraction experiments have confirmed the rhombic structure resulting from these calculations, however, these experimental structures are not sufficiently accurate to critically test the predicted bond lengths and angles. For mixed dimers more precise information may be expected from microwave rotational spectra. In the Berlin laboratory two different techniques have been employed in the rotational study of LiFNaF: a seeded beam with a rotational temperature of about 25 K and cooling by collision in a cold diffusive cell to about 100 K. In the frequency range form 75 to 112 GHz, more than 90 transitions of $^{6}LiFNaF$ and $^{7}LiFNaF$ have been assigned. Due to the high J and K states involved, only a few transitions exhibited partially resolved hyperfine structure from the $^{23}Na$ quadrupolar nucleus. In order to resolve the hyperfine spectum we have used the Fourier-transform microwave (FTMW) spectrometer equiped with NdYAG laser for laser ablation of solid samples at NIST. It is difficult to determine the rotational temperature in the pulsed-beam FTMW spectrometer since only a few rotational states are populated and transitions are widely separated in frequency. The spectra observed in both laboratories were extremely weak in part due to the warmer rotational temperature. In addition to the rotational and hyperfine measurements, we have also examined the Stark effect on $^{7}LiFNaF$ to obtain the dipole moment. The structure resulting from the fit of $I_{a}$ and $I_{b}$ for the two isotopic species is in excellent agreement with a recent ab initio $calculation^{1}$. en_US dc.format.extent 98001 bytes dc.format.mimetype image/jpeg dc.language.iso English en_US dc.publisher Ohio State University en_US dc.title ALKALI HALIDE DIMERS: MICROWAVE SPECTRUM OF LiFNaF en_US dc.type article en_US
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