An Etymological Dictionary of Astronomy and Astrophysics
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An extension of the → Einstein model accounting for → specific heats, based on the concept of → elastic waves in → crystals. In this model specific heat is given by: C_V = 9R[(4/x²)∫ y²/(e^y - 1)dy - x/(e^x - 1)], integrating from 0 to x, where R is the → gas constant, k is → Boltzmann's constant, x = hν_max/k, and y = hν/k. The parameter T_D = hν_max/k is the characteristic → Debye temperature of the crystal. At low temperatures the specific heat prediction by this model is in good agreement with observations (→ Debye law), in contrast to Einstein's model.

→ debye; → temperature.