Effects of Temperature and Pressure on the Magnetic Properties of La1-xPrxCoO3

authors	Panfilov, AS; Lyogenkaya, AA; Grechnev, GE; Pashchenko, VA; Vasylechko, LO; Hreb, VM; Kovalevsky, AV
nationality	International
journal	PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
author keywords	electronic structure calculations; high-pressure effects; magnetic measurements; RCoO(3)compounds; spin crossover
keywords	SPIN-STATE TRANSITION; LACOO3; SUSCEPTIBILITY; PARAMAGNETISM; ANOMALIES; BEHAVIOR; PHASE; LA
abstract	For La(1-x)Pr(x)CoO(3)cobaltites (x = 0, 0.1, 0.2, and 0.3), the dependence of magnetic susceptibility chi(T)is studied in the temperature range 5-400 K. Also, the crystal structure of these cobaltites is investigated, and the effect of pressure up to 2 kbar on their susceptibility is measured atT=78, 150, and 300 K. The specific dependencies chi(T)and the large negative pressure effect are assumed to arise from Co(3+)ions contribution to the total susceptibility evaluated using La(1-x)Pr(x)AlO(3)as a reference system. The obtained experimental data on temperature and pressure effects in magnetism are analyzed within a two-level model with energy gap Delta between the ground state of the system with zero spin of Co(3+)ions and the excited higher-spin state. In this model, magnetism of Co(3+)ions is determined by the temperature-induced population of the excited state, and magnitude of the pressure effect is governed by the volume dependence of Delta. The results of the analysis, supplemented by the theoretical calculations of the electronic structures of LaCoO(3)and PrCoO3, indicate significant increase in Delta with decrease in the unit cell volume both under hydrostatic pressure and by substituting La with Pr having a smaller ionic radius.
publisher	WILEY-V C H VERLAG GMBH
issn	0370-1972
isbn	1521-3951
year published	2020
volume	257
issue	9
digital object identifier (doi)	10.1002/pssb.202000085
web of science category	Physics, Condensed Matter
subject category	Physics
unique article identifier	WOS:000545401400001