"Shape-Dependent" Specific Heat of Cerous Magnesium Nitrate

Abstract

The specific heat of two spheres and of one cylinder of compacted powdered cerous magnesium nitrate has been measured from $T^{*}=3.5\mathrm{} \mathrm{to} 20$ mK. Above 6.5 mK a correction of +0.3 mK must be added to convert $T^{*}\left(\mathrm{sphere}\right)$ to the thermodynamic temperature $T$, and +1.1 mK to convert $T^{*}\left(\mathrm{cylinder}\right)$ to $T$. Below 6.5 mK, $T^{*}\left(\mathrm{sphere}\mathrm{of}\mathrm{powder}\right)+0.3=T^{*}\left(\mathrm{cylinder}\mathrm{of}\mathrm{powder}\right)+1.1\mathrm{} \mathrm{mK}=T^{*}(\mathrm{s}\mathrm{i}\mathrm{n}\mathrm{g}\mathrm{l}\mathrm{e}-\mathrm{c}\mathrm{r}\mathrm{y}\mathrm{s}\mathrm{t}\mathrm{a}\mathrm{l}\mathrm{s}\mathrm{p}\mathrm{h}\mathrm{e}\mathrm{r}\mathrm{e})+\ominus \left(\mathrm{Weiss}\mathrm{constant}\right)$. The specific heat of cerous magnesium nitrate is given by $\frac{C}{\mathrm{nR}}=\frac{6.4}{T^2}-\frac{12}{T^3}$.