Antiferromagnetic order and the structural order-disorder transition in the Cd6Ho quasicrystal approximant

TitleAntiferromagnetic order and the structural order-disorder transition in the Cd6Ho quasicrystal approximant
Publication TypeJournal Article
Year of Publication2013
AuthorsKreyssig A, Beutier G, Hiroto T, Kim MG, Tucker GS, De Boissieu M, Tamura R, Goldman AI
Journal TitlePhilosophical Magazine Letters
Volume93
Pages512-520
Date Published09
Type of ArticleArticle
ISBN Number0950-0839
Accession NumberWOS:000323409700003
Keywordsantiferromagnetism, approximant, phase, quasicrystal, scattering, X-ray resonant magnetic
Abstract

It has generally been accepted that the orientational ordering of the Cd-4 tetrahedron within the Cd6R quasicrystal approximants is kinetically inhibited for R=Ho, Er, Tm and Lu by steric constraints. Our high-resolution X-ray scattering measurements of the Cd6Ho quasicrystal approximant, however, reveal an abrupt (first-order) transition to a monoclinic structure below T-S=178K for samples that have aged' at room temperature for approximately one year, reopening this question. Using X-ray resonant magnetic scattering at the Ho L-3-edge we have elucidated the nature of the antiferromagnetic ordering below T-N=8.5K in Cd6Ho. The magnetic Bragg peaks are found at the charge forbidden H+K+L=2n+1 positions, referenced to the high-temperature body-centred cubic structure. In general terms, this corresponds to antiferromagnetic arrangements of the Ho moments on adjacent clusters in the unit cell as previously found for Cd6Tb.

URL<Go to ISI>://WOS:000323409700003
DOI10.1080/09500839.2013.815375