Debye Temperature

Debye temperature

[də′bī ′tem·prə·chər]
(solid-state physics)
The temperature θ arising in the computation of the Debye specific heat, defined by k θ = h ν, where k is the Boltzmann constant, h is Planck's constant, and ν is the Debye frequency. Also known as characteristic temperature.

Debye Temperature

 

a physical constant of matter that characterizes numerous properties of solids, such as specific heat, electric conductivity, thermal conductivity, broadening

Table 1
MetalθpSemiconductoθDDielectricθo
Hg...............60–90...............Sn (gray)...............212AgBr150
Pb...............94.5...............Ge...............366NaCI320
Na...............160...............Si...............658Diamond1,850
Ag...............225............... 
W...............270............... 
Cu...............339............... 
Fe...............467............... 
Be...............1,160............... 

of X-ray spectral lines, and elastic properties. The concept was first introduced by P. Debye in his theory of specific heat. The Debye temperature is defined by the equation

θD = h vD/k

where k is Boltzmann’s constant, h is Planck’s constant, and vD is the maximum frequency of the vibrations of a solid’s atoms. The Debye temperature indicates the approximate temperature limit below which quantum effects may be observed. At temperatures T ≫ θD the specific heat of a crystal consisting of atoms of one type at constant volume is Cr = 6 cal (°C. mole)-1, which agrees with Dulong and Petit’s law. At T ≪ θD the specific heat is proportional to (Γ/θp,)3 (the Debye T3 approximation).

Typical values of the Debye temperature for some substances are given in degrees Kelvin in Table 1.

References in periodicals archive ?
However, the coefficient of thermal expansion [beta](T) slightly depends on the temperature above the Debye temperature, and this is the reason of nonlinearity of the deformation.
D] is the Debye temperature of the solid, T is the absolute temperature, and R is the universal gas constant (8.
Because the Debye temperature of graphite is high compared to the temperature range of interest (0 to 300K), the above approximate equation is used in the current calculations to estimate the specific heat of the carbon fiber composite overwrap on the tank.
As a result, Debye temperature would increase due to localization of heat energy in the Brillouin zone, and the calculated specific heat capacities showed almost no changes after cation exchange.
The interest in the calculation of the Debye temperature has been increasing in both semi- empirical and theoretical phase diagram calculations since the Debye model offers a simple but very effectual method to explain the phonon contribution to the Gibbs energy of crystalline phases.
0] we should indicate the Debye temperature [[theta].
B] almost coincide with the Debye temperature [[THETA].
Our computed acoustic Debye temperature, 1217 K, is about 20 % lower than the handbook calorimetric value.
Heat-conductivity of glasses at temperatures below the debye temperature.