Magnetoelastic Properties of La$\text{}_{0.744}$Ba$\text{}_{0.186}$MnO$\text{}_{3}$ Single Crystals

Magnetoelastic properties of La$\text{}_{0.744}$Ba$\text{}_{0.186}$MnO$\text{}_{3}$ single crystals have been studied. The basic magnetoelastic constants of the crystal have been estimated using the data of magnetostriction and magnetization measurements, which have been carried out in [010] and [110] crystallographic directions in a wide temperature range from 10 K to 150 K. The anomaly of the thermal expansion has been observed at about 185 K. Near this anomaly two almost degenerated phase transitions have been observed. One of these transitions may be related to the structural phase transition, while the second one to the occurrence of spontaneous strains. The magnetostriction of La$\text{}_{0.744}$ Ba$\text{}_{0.186}$MnO$\text{}_{3}$ single crystal seems to arise due to the effect of applied field on the spontaneous strains.