Molecule-like cluster magnetism and cationic order in the new hexagonal perovskite Ba4Sn1.1Mn2.9O12
Junkun Wu1, Xiaohui Yan1, Wenbin Guo1
1MOE Key Laboratory of New Processing Technology for Nonferrous Metal and Materials, Guangxi Key Laboratory of Optic and Electronic Materials and Devices, College of Materials Science and Engineering, Guilin University of Technology Guilin 541004 P. R. China congling.yin@glut.edu.cn.
Abstract:
The new hexagonal perovskite phase of composition Ba4Sn1.1Mn2.9O12 has been synthesized by solid-state reactions at 1673 K. The crystal structure has been investigated using X-ray and neutron diffraction. The hexagonal perovskite structure has an ordered arrangement of Sn and Mn ions on the corner-sharing octahedral centers and the face-sharing octahedral centers respectively. Short Mn-Mn distances have been evidenced in the face-sharing trimer of MnO6 octahedra. The magnetic susceptibility shows magnetic cluster behavior, with cluster formation temperature ∼220 K. Antiferromagnetic order has been observed at T N ∼ 6 K. Ba4Sn1.1Mn2.9O12 is a semiconductor with a transport activation energy of 0.61 eV.
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