Beryllium Debye temperature

The Debye temperature Bd for metals varies from 88 K for lead to 1000 K for beryllium. Values of Bo are often also assigned to chemical compounds,... 

The free energy due to harmonic lattice vibrations (or equivalently the Debye temperature) is approximately the same for bcc, fee, and hep structures but with a significant tendency for the bcc value to be a few percent lower. The more open bcc structure has a transverse phonon mode with a particularly low frequency which causes a more rapid decrease in the free energy with temperature. On cooling, sodium and lithium transform partially from bcc to hep at very low temperatures (0.1-0.2 Tm). Calcium, strontium, beryllium, and thallium transform to a bcc phase at high temperatures (0.66-0.98 Tm) when there is a considerable anharmonic contribution to the free energy. 

The empirical Dulong-Petit rule states that at room temperature all solid elements exhibit the same molar heat capacity, which is roughly equal to three times the ideal gas constant. This is, however, not true for all solids (e.g., diamond, silicon, boron, and beryllium), but it gives a good order of magnitude for engineers and scientists in the absence of data, especially in the field or at the plant. This behavior was later confirmed theoretically by the work of Einstein and Debye, who demonstrated that at temperatures above the Debye temperature of the element (T ), the molar heat capacity of solids tends to 3R ... 

Solution. Assume that the Debye temperature for copper is applicable to beryllium copper ... 

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