Crystal and Magnetic Structure of CaCo{1.86}As2 Studied by X-ray and Neutron Diffraction

D. G. Quirinale; V. K. Anand; M. G. Kim; Abhishek Pandey; A. Huq; P. W. Stephens; T. W. Heitmann; A. Kreyssig; R. J. McQueeney; D. C. Johnston; A. I. Goldman

doi:10.1103/physrevb.88.174420

arXiv · 1310.2587

Crystal and Magnetic Structure of CaCo{1.86}As2 Studied by X-ray and Neutron Diffraction

D. G. Quirinale·V. K. Anand·M. G. Kim·Abhishek Pandey·A. Huq·P. W. Stephens·T. W. Heitmann·A. Kreyssig·R. J. McQueeney·D. C. Johnston·A. I. Goldman

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Abstract

Neutron and x-ray diffraction measurements are presented for powders and single crystals of CaCo{1.86}As2. The crystal structure is a collapsed-tetragonal ThCr2Si2-type structure as previously reported, but with 7(1)% vacancies on the Co sites corresponding to the composition CaCo{1.86(2)}As2. The thermal expansion coefficients for both the a- and c-axes are positive from 10 to 300 K. Neutron diffraction measurements on single crystals demonstrate the onset of A-type collinear antiferromagnetic order below the Neel temperature TN = 52(1) K with the ordered moments directed along the tetragonal c-axis, aligned ferromagnetically in the ab-plane and antiferromagnetically stacked along the c-axis.

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D. G. Quirinale, V. K. Anand, M. G. Kim, Abhishek Pandey, A. Huq, P. W. Stephens, T. W. Heitmann, A. Kreyssig, R. J. McQueeney, D. C. Johnston, A. I. Goldman. 2013-10-09. Crystal and Magnetic Structure of CaCo{1.86}As2 Studied by X-ray and Neutron Diffraction. https://doi.org/10.1103/physrevb.88.174420

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