| Abstract
| - X-ray magnetic circular dichroism (XMCD) measurements on Yb14MnSb11 provide experimentalevidence of a moment of 5 μB on Mn, with partial cancellation by an opposing moment on the Sb4 cagesurrounding each Mn ion. The compound is isostructural to Ca14AlSb11, with Mn occupying the Al site inthe AlSb49- discrete tetrahedral, anionic unit. Bulk magnetization measurements indicate a saturation momentof 3.90 ± 0.02 μB/formula unit consistent with four unpaired spins and implying a Mn3+, high-spin d4 state.XMCD measurements reveal that there is strong dichroism in the Mn L23 edge, the Sb M45 edge shows aweak dichroism indicating antialignment to the Mn, and the Yb N45 edge shows no dichroism. Comparisonsof the Mn spectra with theoretical models for Mn2+ show excellent agreement. The bulk magnetization canbe understood as Mn with a moment of 5 μB and a 2+ configuration, with cancellation of one spin by anantialigned moment from the Sb 5p band of the Sb4 cage surrounding the Mn.
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