Structural, magnetic, dielectric and mechanical properties of (Ba,Sr)MnO${}_3$ ceramics

Abstract

Ceramic samples, produced by conventional sintering method in ambient air, 6H-SrMnO${}_3$(6H-SMO), 15R-BaMnO${}_3$(15R-BMO), 4H-Ba${}_{0.5}$Sr${}_{0.5}$MnO${}_3$(4H-BSMO) were studied. In the XRD measurements for SMO the new anomalies of the lattice parameters at 600-800 K range and the increasing of thermal expansion coefficients with a clear maximum in a vicinity at 670 K were detected. The N$\acute{e}$el phase transition for BSMO was observed at $T_N$=250 K in magnetic measurements and its trace was detected in dielectric, FTIR, DSC, and DMA experiments. The enthalpy and entropy changes of the phase transition for BSMO at $T_N$ were determined as 17.5 J/mol and 70 mJ/K mol, respectively. The activation energy values and relaxation times characteristic for relaxation processes were determined from the Arrhenius law. Results of ab initio simulations showed that the contribution of the exchange correlation energy to the total energy is about 30%.

12 pages, 12 figures

References in corpus (7)

• The SIESTA method for ab initio order-N materials simulation
• Efficient index handling of multidimensional periodic boundary conditions
• Selfconsistent order-N density-functional calculations for very large systems
• Magnetodielectric coupling in Mn3O4
• Strong spin-phonon coupling in infrared and Raman spectra of SrMnO3
• Improper ferroelectricity and multiferroism in 2HBaMnO${}_3$
• Neutron Scattering Studies of the Ferroelectric Distortion and Spin Dynamics in the Type-1 Multiferroic Perovskite Sr0.56Ba0.44MnO3

Cited by in corpus (1)

• Combinatorial screening of crystal structure in Ba-Sr-Mn-Ce perovskite oxides with ABO3 stoichiometry