TY - JOUR

T1 - Irrelevance of atomic masses for Debye-Waller B values in the limit of high temperatures

AU - Huiszoon, C.

AU - Groenewegen, P.P.M.

PY - 1972

Y1 - 1972

N2 - An expression that approximates Debye-Waller B values by a sum of three terms is derived from the theory of lattice dynamics in the harmonic approximation. For cubic crystals (M is the mass of the th atom in the unit cell): B = T + 22h2/3k TM + /M2T3, where T D/2 and and are constants, depending on interatomic forces only. It is shown that for temperatures above the Debye temperature D of the lattice, the second and third terms in the above expression can be neglected. From this, it follows that above the Debye temperature Debye-Waller B values become independent of the atomic masses. Consequently, the heavier atoms in a lattice do not necessarily have the smaller B values.

AB - An expression that approximates Debye-Waller B values by a sum of three terms is derived from the theory of lattice dynamics in the harmonic approximation. For cubic crystals (M is the mass of the th atom in the unit cell): B = T + 22h2/3k TM + /M2T3, where T D/2 and and are constants, depending on interatomic forces only. It is shown that for temperatures above the Debye temperature D of the lattice, the second and third terms in the above expression can be neglected. From this, it follows that above the Debye temperature Debye-Waller B values become independent of the atomic masses. Consequently, the heavier atoms in a lattice do not necessarily have the smaller B values.

U2 - 10.1107/S0567739472000361

DO - 10.1107/S0567739472000361

M3 - Article

SN - 0567-7394

VL - 29

SP - 170

EP - 172

JO - Acta crystallographica Section A: Crystal physics, diffraction, theoretical and general crystallography

JF - Acta crystallographica Section A: Crystal physics, diffraction, theoretical and general crystallography

ER -