Crystal and magnetic structures of Sr4MMn2O9 (M=Cu or Zn) |
| |
Authors: | Caroline A. Moore |
| |
Affiliation: | Inorganic Chemistry Laboratory, Oxford University, South Parks Road, Oxford OX1 3QR, UK |
| |
Abstract: | The crystal and magnetic structures of Sr4MMn2O9 (M=Cu, Zn) have been refined from neutron powder diffraction data. These trigonal compounds (space group P321, a=9.5918(1), c=7.8114(1) Å (Cu); a=9.5894(1), c=7.5039(1) Å (Zn)) are n=3 members of the series A3n+3MnBn+3O6n+9, with each unit cell containing three offset [001] polyhedral chains, each of which ideally contains a 1:1 ratio of B2O9 units and MO6 trigonal prisms. In fact anti-site disorder between Mn and M is observed, and for M=Cu the cations are disordered off the center of the prism towards a rectangular face. Both compositions show 3D anti-ferromagnetic order at 1.6 K, with an ordered magnetic moment of 1.91(6) (M=Cu) or 1.8(1) (M=Zn) μB per Mn. No ordered magnetic moment was detected on the trigonal prismatic site in either compound, consistent with the observed temperature dependence of the magnetic susceptibility. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|