dc.creator Stidham, Howard D. en_US dc.creator Farrell, H. H en_US dc.date.accessioned 2006-06-15T16:32:27Z dc.date.available 2006-06-15T16:32:27Z dc.date.issued 1966 en_US dc.identifier 1966-K-11 en_US dc.identifier.uri http://hdl.handle.net/1811/15046 dc.description Author Institution: Department of Chemistry, University of Massachusetts en_US dc.description.abstract The pure chlorine nuclear quadrupole resonance (NQR) absorption frequencies of several crystalline chlorobenzenes and their deuterium containing analogues have been measured at various temperatures between $77^{\circ} K$ and their respective melting points. Raman spectra of single crystals of some of these compounds have been obtained near room temperature. Thermal averaging of chlorine quadrupolar parameters is dominated by librational lattice modes and low frequency intramolecular chlorine bending motions. The greater mass of the deuterium containing compounds produces smaller vibrational amplitudes and less effective averaging of quadrupolar parameters, leading to prediction of higher NQR frequency for any deuterated compound than for the corresponding hydrogen compound at any temperature. In earlier work, the opposite effect was observed. When deuterium is substituted for hydrogen, both increases and decreases of NQR frequency are observed in the present work; in the case of p-dichlorobenzene, the NQR frequency decreases in the monoclinic phase but increases in the $\gamma$ phase. The theoretical discussion given attempts to correlate the Raman and NQR data obtained without invoking the hypothesis of deuterium substitution induced electronic structure changes. en_US dc.format.extent 181996 bytes dc.format.mimetype image/jpeg dc.language.iso English en_US dc.publisher Ohio State University en_US dc.title EFFECT F DEUTERIUM SUBSTITUTION ON VIBRATIONAL AVERAGING OF CHLORINE NUCLEAR QUADRUPOLAR PARAMETERS AT FINITE TEMPERATURES en_US dc.type article en_US
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