Local configurational instability of the lattice near an impurity in a cubic crystal
Badalyan A. G., Baranov P. G., Vikhnin V. S., Khramtsov V. A.
A spontaneous local change in the lattice structure of a cubic crystal near an impurity in a narrow temperature interval has been observed for the first time. The effect is interpreted as the onset of an instability with respect to a quasilocal vibration of symmetry A2 associated with a manganese impurity in a BaF2 crystal.