Thermochromism in (Ba,Sr)-Mn oxides

• Published in: The Journal of physics and chemistry of solids Vol. 63; no. 4; pp. 591 - 595
• Main Authors: Heiras, J., Pichardo, E., Mahmood, A., López, T., Pérez-Salas, R., Siqueiros, J.M., Blanco, O., Castellanos, M.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.04.2002; Elsevier
• Subjects: A. Ceramic; A. Oxides; C. X-ray diffraction; Condensed matter: electronic structure, electrical, magnetic, and optical properties; D. Optical properties; Exact sciences and technology; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Photoluminescence; Physics; A. Ceramic; A. Oxides; C. X-ray diffraction; D. Optical properties; Temperature dependence; Scanning electron microscopy; Barium Manganites; Color; Photoluminescence; Perovskites; XRD; Thermochromism; Hexagonal lattices; Transmission electron microscopy; Strontium Manganites; Transition elements; Sintering; Preparation; Solid state reaction; Thermo-optical effects; Manganese
• ISSN: 0022-3697; 1879-2553
• DOI: 10.1016/S0022-3697(01)00198-6

Manganese based ceramic samples with composition given by the formula MeMnO3 (Me=Ba,Sr) were prepared by solid state reaction. The preparation conditions were varied over a wide range of temperatures and the optimum sintering temperature was obtained. These materials present a change of color at low temperature (at approximately 140K). To find the probable reason for the change of color, the materials have been characterized by various advanced techniques like X-ray diffraction (XRD), photoluminiscence, scanning and transmission electron microscopy (SEM and TEM). Studies were made at room and at low temperature. These thermochromic materials have hexagonal perovskite-like structure.