title: High temperature magnetic ordering in the 4d perovskite SrTcO3.
abstract: 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. Electronic structure calculations reveal extensive mixing between the technetium 4d states and oxygen states proximal to the Fermi level. This hybridization leads to a close relationship between magnetic ordering temperature and moment formation in SrTcO3.
authors.affiliation: NIST Center for Neutron Research, National Institute of Science and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20889, USA.
authors.forename: Efrain E
authors.initials: EE
authors.lastname: Rodriguez
authors.forename: Frédéric
authors.initials: F
authors.lastname: Poineau
authors.forename: Anna
authors.initials: A
authors.lastname: Llobet
authors.forename: Brendan J
authors.initials: BJ
authors.lastname: Kennedy
authors.forename: Maxim
authors.initials: M
authors.lastname: Avdeev
authors.forename: Gordon J
authors.initials: GJ
authors.lastname: Thorogood
authors.forename: Melody L
authors.initials: ML
authors.lastname: Carter
authors.forename: Ram
authors.initials: R
authors.lastname: Seshadri
authors.forename: David J
authors.initials: DJ
authors.lastname: Singh
authors.forename: Anthony K
authors.initials: AK
authors.lastname: Cheetham