Not only do antiferromagnets make up the vast majority of magnetically ordered substances (magnets), It has many specific properties,. They are unique to ,. in all fields of magnetophysics - magnetism proper (linear and nonlinear), Galvanomagnetism , magnetooptics, magnetoacoustics, Acousto-optics and p. Systematic consideration of all these properties at a level assuming knowledge only within the general course of physics, and is devoted to the book For students and teachers, researchers and engineers-developers of physico-technical profile, interested in the application of new physical phenomena in solid-state electronics Many theoretical predictions are designed to stimulate the experimental discovery of such new phenomena. The book can serve as an additional guide to the study of magnets in terms of symmetry, crystal chemistry and magnetic .