Beschreibung:
<jats:p>Effects of defects on dipole interactions in a simple cubic lattice are calculated using the spherical model developed by Berlin and Thomsen, Lax, and others. When the concentration of defects is small, thermodynamical functions are linearly dependent on the concentration. The Curie temperature in the three-dimensional lattice is raised or lowered linearly with the concentration according to whether the defects have stronger or weaker dipole interactions with their neighbors than the interactions which the rest of atoms have. Lattice vacancies also reduce the Curie temperature. The specific heat and electric susceptibility of defect lattice are calculated. In the presence of an homogeneous electric field, there exists a critical field which is influenced by defects.</jats:p>