Crystallographic phases in La2/3Ba1/3MnO3: temperature transformations and relation to magnetism

Singularities of magnetic and elastic characteristics of La2/3Ba1/3MnO3: Analysis of martensitic kinetics

“…The susceptibility hysteresis loop is asymmetric: its high temperature extent ($140 K) is much greater than the low temperature one ($20 K). This is in accordance with the neutron diffraction data [5,6] and is attributed to the high temperature of the reverse martensitic transformation that finishes at $370 K when heating (strictly speaking the A f temperature for the present samples can be slightly different from 370 K because of certain difference between their oxygen content and that of the samples have been studied in [5,6]; see next section). 3.…”

“…[5,6] below the room temperature crystal structure of La 2/3 Ba 1/3 MnO 3 manganite represents a mixture of the high temperature rhombohedral R3c phase (austenite) and the low temperature orthorhombic phase Imma (martensite) as a result of martensitic phase transformation. It occurs over a wide range of temperatures [5,6] that is typical for transformations of such type [7,30]. Note, that on cooling, a martensitic transformation starts at the martensite start temperature M s , and finishes at the martensite finish temperature M f .…”

“…Authors of the Refs. [5,6] observed process of exchange of the crystallographic phases in La 2/3 Ba 1/ 3 MnO 3 in the wide temperature interval, and noted, that the phenomenon resembled a martensitic transformation. But it would be advisable to confirm the supposition by additional experiments.…”

“…Besides, the compound is known to reveal interesting phenomena accompanying the structural phase transformation of martensitic type in 200 K temperature region due to the strong interplay between electronic structure, lattice and magnetic properties [5,6].…”

Structural first-order transformation in La2/3Ba1/3MnO3: ESR study

“…The first-order structural transformations in manganites which are not associated with charge-ordering are still not enough understood, although experiments on La 1 À x Sr x MnO 3 [19][20][21][22] and La 1 À x Ba x MnO 3 (x¼0.2, 0.33) [16,[23][24][25][26] many interesting peculiarities of their behavior associated with the MT, such as the dependence of the transformation temperature T s on magnetic field and hydrostatic pressure, a wide temperature range of the phases coexistence and nonequilibrium thermodynamics.…”