Low Temperature Physics: 42, 149 (2016); https://doi.org/10.1063/1.4942583
Fizika Nizkikh Temperatur: Volume 42, Number 2 (February 2016), p. 198-201    ( to contents , go back )

Barium manganite Ba6Mn24O48 x-ray studies in the magnetic transition area

I.V. Legchenkova, А.I. Prokhvatilov, Yu.Е. Stetsenko, and К.А. Yagotintsev

B. Verkin Institute for Low Temperature Physics and Engineering National Academy of Sciences of Ukraine 47 Nauki Ave., Kharkiv, 61103, Ukraine
E-mail: prokhvatilov@ilt.kharkov.ua
pos Анотація:

Received September 7, 2015

Abstract

The powder x-ray diffraction method was used on polycrystalline and compacted barium manganite Ba6Mn24O48 powder at room and low temperatures. Significant influence of compacting process, which leads to accumulation of micro- and macrostress in samples, on diffraction pattern determined. Temperature dependences of lattice parameters a and c and linear expansion coefficient of tetragonal phase of basal plane obtained in temperature range 20–100 K. Lattice parameter a abnormal shift and negative linear expansion coefficient αa values detected at magnetic phase transition temperature area 45 K. No peculiarities were observed on с(Т) temperature dependences. Probable cause of such a temperature behavior of barium manganite structure and thermal characteristics assumed to be related to considerable crystal lattice anisotropy.

PACS: 61.05.cp X-ray diffraction;
PACS: 64.70.–p Specific phase transitions;
PACS: 65.40.De Thermal expansion; thermomechanical effects.

Key words: barium manganite Ba6Mn24O48, whisker, powder x-ray diffraction, thermal expansion, magnetic phase transition.

Published online: December 23, 2015

Download 573354 byte View Contents