Structural phase transition in La2/3Ba1/3MnO3 perovskite: Elastic, magnetic, and lattice anomalies and microscopic mechanism

Abstract

Magnetic and charge ordering in nanosized manganites Applied Physics Reviews 1, 031302 (2014) The temperature dependences of the elastic and magnetic properties of polycrystalline perovskite manganite La 2/3 Ba 1/3 MnO 3 were studied using ultrasonic and SQUID magnetometer techniques. The minimum of the temperature-dependent sound velocity v(T) and corresponding maximum of the decrement δ(T) were found in the vicinity of the structural phase transition R3c ↔ Imma at T s ∼ 200 K. Large alterations of v and δ indicate a structural phase transition of the soft mode type. A high sensitivity of dc magnetization to a low uniaxial pressure caused by the softening was found in the T s region. A negative value of the linear thermal expansion coefficient along one of the crystallographic axis was found in the Imma phase near T s . The proposed microscopic mechanism explains the appearance of the soft mode in the vicinity of the structural phase transition temperature associated with the displacement of the manganese atom from the center of the oxygen octahedron. C 2015 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 Unported License. [http://dx

Influence of Ruthenium Doping on the Crystal Structure and Magnetic Properties of Pr0.67Ba0.33Mn1–xRuxO3 Manganites

“…Numerous works have reported the structure of these compounds. Manganite perovskites exhibit a variety of structural formations, such as orthorhombic and rhombohedral formations, depending on the substitution ions and preparation of the compounds [12]. However, unsystematic variations in the magnetic and structural properties of manganites were observed for doped Ru at Mn site compounds.…”