New Mixed Perovskite RCo0.5Cr0.5O3 (R = Dy, Ho, Er) as a Potential Thermoelectric and Sensory Material

Vasyl Hreb1 wasiahreb [at] meta.ua
Leonid Vasylechko1 crystal-lov [at] polynet.lviv.ua
Yurii Prots2 prots [at] cpfs.mpg.de
Andrew Fitch3 fitch [at] esrf.fr
  1. Lviv Polytechnic National University, UKRAINE, Lviv, 12 Bandera St.
  2. Max-Planck-Institut für Chemische Physik fester Stoffe, GERMANY, Dresden Nöthnitzer Str. 40
  3. 3ESRF-The European Synchrotron, FRANCE, CS40220 38043 Grenoble Cedex 9
Abstract 

The mixed earth rare cobaltites and chromites with general formula RCo0.5Cr0.5O3 (R = Dy, Ho, Er) were obtained by solid state reaction in air at 1373 K. Based on high temperature X-ray synchrotron powder diffraction data in range temperature 298 –1273 K abnormal thermal expansion of lattice dimensions was observed. Thermal expansion coefficient showed maxima, which point on insulator-metal transition. Abnormal behavior is associated with changes of spin state of Co3+ ions

Keywords 
perovskite
thermal expansion
lattice parameters
insulator-metal transition
spin state
mixed cobaltites and chromites
spin transition
References 

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