Heat Capacity of Beryllium below 30°K

The heat capacity of high-purity beryllium (R₃₀₀R4.2=1100) was measured from 1.4^∘{}K to 30^∘{}K. The results can be expressed by the sum of contributions proportional to T, T³, and T⁵ with the coefficients (0.1714±{}0.0008) mJ/M(^∘K)², (0.598±{}0.020)×{}10^-3 mJ/M(^∘K)⁴, and (0.18±{}0.04)×{}10^-6 mJ/M(^∘K)⁶, respectively. The Debye theta at 0^∘{}K (Θ₀) is (1481±{}16)^∘{}K. The results are in good agreement with some of the recent lattice-dynamical and band-structure calculations and with Θ₀ derived from elastic constants. Phonon enhancement of the density of states does not appear important in beryllium. The heat capacity is smaller than the work of previous investigators indicated.