High Temperature Magnetic Ordering in the4dPerovskiteSrTcO3

Efrain E. Rodriguez, Frédéric Poineau, Anna Llobet, Brendan J. Kennedy, Maxim Avdeev, Gordon J. Thorogood, Melody L. Carter, Ram Seshadri, David J. Singh, Anthony K. Cheetham
2011 Physical Review Letters  
We present evidence for possibly the highest magnetic ordering temperature in any compound without 3d transition elements. Neutron powder diffraction measurements, at both time-of-flight and constant wavelength sources, were performed on two independently prepared SrTcO3 powders. SrTcO3 adopts a distorted perovskite structure with G-type antiferromagnetic ordering and has a moment of 1.87(4) µB per Tc cation at room temperature with an extraordinarily high Néel point close to 750 • C.
more » ... structure calculations reveal extensive mixing between the technetium 4dstates and oxygen states proximal to the Fermi level. This hybridization leads to a close relationship between magnetic ordering temperature and moment formation in SrTcO3.
doi:10.1103/physrevlett.106.067201 pmid:21405490 fatcat:i2sjuqbyvnfnhlws734y2os3gy