Terahertz laser spectroscopy of the water dimer intermolecular vibrations . II
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چکیده
Terahertz VRT laser spectra of four ~H2O!2 intermolecular vibrations consisting of 362 transitions have been measured between 87 and 108 cm with ca. 2 MHz precision. The results differ both qualitatively and quantitatively from the predictions of dimer potentials tested. The spectra also reveal an ordering of the intermolecular vibrations which differs dramatically from that predicted by normal mode analysis. Strong coupling is indicated between the low barrier tunneling motions and the intermolecular vibrations as well as among different vibrations. In particular the 102.1 cm ~H2O!2 vibration assigned as the acceptor wag (n8) exhibits two types of perturbations. In one of these a component of Ka51 coupling with a tunneling component of Ka50 in the 108 cm 21
منابع مشابه
Terahertz laser spectroscopy of the water dimer intermolecular vibrations .
Terahertz laser VRT spectra of the water dimer consisting of 731 transitions measured with an average precision of 2 MHz and involving four ~D2O!2 intermolecular vibrations ~one previously published! have been measured between 65 and 104 cm. The precisely determined energy level patterns differ both qualitatively and quantitatively from the predictions of several dimer potentials tested, and re...
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