(a) Imaginary part of normalized dielectric permittivity of glycerol (Ref. 19) (black lines). For , we show our new results (black crosses) of a time domain spectrometer operating in the discharging mode, allowing to suppress the conductivity contribution, which otherwise is rather strong, cf. data at (blue line); for comparison with the NMR susceptibility (red points) is shown indicating the same time constant; and high-frequency power law (excess wing) is indicated by dashed line. (b) Normalized susceptibility spectra as obtained from depolarized light scattering (Ref. 9).
(a) Dispersion of the spin-lattice relaxation time as measured by the Bayreuth spectrometer for temperatures (in K) as indicated (selected data sets); lines indicate guides to the eye. (b) Conversion of the data in (a) along Eq. (6) into the susceptibility representation; thick solid (red) line, interpolation around the relaxation maximum at applying a Cole–Davidson susceptibility.
Susceptibility data obtained from the spin-lattice relaxation time as measured by a homebuilt Darmstadt spectrometer allowing to measure low temperatures (in K) as indicated (selected data sets); lines are guides to the eye.
Time constants of the process obtained from the construction of the master curves in Figs. 5 and 7 applying the probing techniques NMR (Bayreuth and Darmstadt), dielectric spectroscopy (DS), and depolarized LS.
Master curves obtained from dielectric spectroscopy, cf. Fig. 1(a) (black points) and from NMR relaxation data, cf. Figs. 2(b) and 3 (red crosses and blue plus, respectively), spectra from the temperature range as indicated were used; (dashed line) interpolation of relaxation maximum with a Cole–Davidson function using .
Susceptibility master curve of glycerol in the low frequency range as compiled by NMR [colored circles, each color refers to another temperature; data from Fig. 2(b)], DS (black crosses) and LS (blue plus); temperature range used as indicated; and dashed lines show power-law interpolations.
Comparison of the susceptibility master curves of glycerol compiled from NMR (cf. Fig. 2), dielectric spectroscopy [(DS) [cf. Fig. 1(a)] and depolarized light scattering (LS) [cf. Fig. 1(b)]; temperature range used as indicated; and (red) full lines, interpolations assuming a relaxation described by a sum of two Cole–Davidson functions with and .
Dielectric [lines this work and crosses (Ref. 46)] and NMR susceptibility [cf. Eq. (9)] (red circles) spectra compared to each other at temperatures below ; the NMR data are scaled by a single factor .
(a) Temperature dependence of the NMR susceptibility at (red circles) [cf. Eq. (9)] as measured in the present work compared to one obtained from the data reported by Akagi and Nakamura (Ref. 61) (open circles) and the imaginary part of the dielectric permittivity (black crosses), both scaled by a single factor . For comparison the quantity from Ref. 61 are shown (full triangle). (dashed straight line) exponential temperature dependence with , cf. Eq. (12). (b) Susceptibilities as in (a) compared on logarithmic temperature scale.
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