Translational and librational motions of H2O molecules in a frequency region lying below 1000 cmminus;1have been previously examined for various configurations using the inelastic scattering of lowhyphen;energy neutrons (0.005 eV). In the present work, H2O motions are studied in cases where neither of the lone electron pairs on the oxygen of the H2O molecule is specifically directed (K2C2O4middot;H2O), where the lone pairs are directed toward two monovalent metal ions (KFmiddot;2 H2O), where the H2O molecule has a single orientation Ba(ClO3)2middot;H2O or two distinct, equally probable orientations (Li2SO4middot;H2O). The neutron spectrum of K2C2O4middot;H2O typically exhibits torsional peaks at 500, 605, and 700 cmminus;1which shift by 1.35 in frequency upon deuteration. They are well separated from a sharp peak at 195 cmminus;1which is assigned to the stretching motion of an H2O molecule H bonded to the oxalate ion and does not shift upon deuteration. The neutron spectra are discussed and compared with the results of proton magnetic resonance, Raman, and infrared measurements.
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