Study of the anomalies near 75°C in LiNbO3

Abstract
The anomaly of LiNbO3 in the vicinity of 75°C has been studied by various X-ray diffraction methods. An abrupt change of axial ratio (c/a) was measured. Internal friction peak associated with this change shows characteristic of first order phase transition. A step-like change in all elastic constant Cij occurs near 75°C.