Fig. : RRUFF ID R040007 Raman spectrum (0° depolarized) in the upper part and a detail of it in the lower part, both in semi log scale. Fig. : Upper part: best fit (blue) onto RRUFF ID R040007 Raman spectrum (red), when a q-Gaussian is used. In the lower part the best fit is in green, and two q-Gaussians are used. The minimized sums of the squares of the deviations are equal to 8.0 x 10 -4 and 5.7 x 10 -4 , respectively (sums from 100 to 510).