Concentration fluctuations static distribution

The third model assumes that the concentration fluctuations are long lived but not static. The dotted line in Fig. 12 shows good agreement with the data assuming a lifetime of 5 ps for the concentration fluctuations. A range of lifetimes from 4 to 7 ps is compatible with the data. This model not only agrees with the Raman echo data, it is also matches the FID and Raman line shape and peak position data as well. The lifetime found in the Raman echo implies that the Gaussian component of the line shape (4.25 cm-1) is actually motionally narrowed from the full distribution of frequencies (5.15 cm-1). 

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