The Temperature Dependence of NQR Spectra

In NMR spectroscopy of nuclei with spin 7=1/2 certain features of the spectrum change with temperature. It is mainly the line width and the fine stru- 

Quite a different situation is experienced in NQR spectroscopy. Dehmelt and Kriiger (1950/1951) 3-6 found that the temperature dependence of NQR frequencies in organic materials is considerable. For instance, the temperature coefficient of i (35Cl) for chlorine bonded to carbon atoms is found to be in the range 

Near the solid state transformation points the isobaric temperature coefficients can reach very high values. An example of such behaviour is the temper- 

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In the discussion of NQR results in the frame of the Townes-Dailey theory, the influence of temperature on NQR frequencies is normally ignored. The temperature dependence of NQR spectra is considered here as a crystal field effect and in the following we shall discuss some of its aspects. 

The question of primary interest here is the effect of the temperature dependence of NQR spectra on the determination of the charge distribution within the... 

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