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Title: Triangular Arrangement of Ferromagnetic Iron Chains in the High‐ T C Ferromagnet TiFe 1−x Os 2+x B 2
Abstract

Transition‐metal borides (TMBs) containing Bn‐fragment (n>3) have recently gained interest for their ability to enable exciting magnetic materials. Herein, we show that the B4‐containing TiFe0.64(1)Os2.36(1)B2is a new ferromagnetic TMB with a Curie temperature of 523(2) K and a Weiss constant of 554(3) K, originating from the chain ofM3‐triangles (M=64 %Fe+36 %Os). The new phase was synthesized from the elements by arc‐melting, and its structure was elucidated by single‐crystal X‐ray diffraction. It belongs to the Ti1+xOs2−xRuB2‐type structure (space groupP2 m, no. 189) and contains trigonal‐planar B4boron fragments [B−B distance of 1.87(4) Å] interacting withM3‐triangles [M–Mdistances of 2.637(8) Å and 3.0199(2) Å]. The experimental results were supported by computational calculations based on the ideal TiFeOs2B2composition, which revealed strong ferromagnetic interactions within and between the Fe3‐triangles. This discovery represents the first magnetically ordered Os‐rich TMB, thus it will help expand our knowledge of the role of Os in low‐dimensional magnetism of intermetallics and enable the design of such materials in the future.

 
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NSF-PAR ID:
10374647
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Chemistry – A European Journal
Volume:
28
Issue:
42
ISSN:
0947-6539
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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