Crystal Structure and Antiferromagnetic Order inNdFeAsO1?xFx(x=0.0and 0.2) Superconducting Compounds from Neutron Diffraction Measurements

Qiu, Y. and Bao, Wei and Huang, Q. and Yildirim, T. and Simmons, J. M. and Green, M.A. and Lynn, J. W. and Gasparovic, Y. C. and Li, J. and Wu, T. and Wu, G. and Chen, X. H. (2008) Crystal Structure and Antiferromagnetic Order inNdFeAsO1?xFx(x=0.0and 0.2) Superconducting Compounds from Neutron Diffraction Measurements. Physical Review Letters, 101 (25). p. 257002. ISSN 0031-9007. (doi:https://doi.org/10.1103/PhysRevLett.101.257002) (The full text of this publication is not currently available from this repository. You may be able to access a copy if URLs are provided)

Abstract

The transition temperature T C ?26??K of the recently discovered superconductor LaFeAsO 1?x F x is extremely sensitive to the lanthanide ion, reaching 55 K for the Sm containing oxypnictides. Therefore, it is important to determine how the moment on the lanthanide affects the overall magnetism in these systems. Here we report a neutron diffraction study of the Nd oxypnictides. Long-ranged antiferromagnetic order is apparent in NdFeAsO below 1.96 K. Rietveld refinement shows that both Fe and Nd magnetic ordering are required to describe the observed data with the staggered moment 1.55(4)? B /Nd and 0.9(1)? B /Fe at 0.3 K. The other structural properties such as the tetragonal-orthorhombic distortion are found to be very similar to those in LaFeAsO. Neither the magnetic ordering nor the structural distortion occur in the superconducting sample NdFeAsO 0.80 F 0.20 at any temperatures down to 1.5 K.

Item Type:	Article
Subjects:	Q Science > QC Physics > QC173.45 Condensed Matter Q Science > QD Chemistry > QD478 Solid State Chemistry
Divisions:	Faculties > Sciences > School of Physical Sciences > Functional Materials Group
Depositing User:	Giles Tarver
Date Deposited:	19 Oct 2015 14:10 UTC
Last Modified:	22 Oct 2015 08:59 UTC
Resource URI:	https://kar.kent.ac.uk/id/eprint/51081 (The current URI for this page, for reference purposes)