The superconductivity of Th7.1(Fe, Co)3, Th7.1(Co, Ni)3 and Th7.1(Fe, Ni)3 pseudo-binary compounds is reported. An unusual peak-and-valley structure is observed in the compositional variations of the superconducting transition temperatures. The same features in the data for the combined Th7.1(Fe, Co)3 and Th7.1(Co, Ni)3 systems are reproduced, although attenuated, in those for the Th7.1(Fe, Ni)3 system. It is argued that in the Th7X3 compounds with D102 structure the superconductivity is due to Th 6dbands.
|Number of pages||4|
|State||Published - Dec 2 1985|
Bibliographical noteFunding Information:
ThvFe3, Th7Co 3 and Th7Ni 3 are the only Th-rich compounds known to form with iron group elements. They all have the hexagonal D102 structure and become superconductors with transition temperatures T c of about 2 K \[1\]. The Fe, Co and Ni atoms are isolated from one another in cages of Th atoms, and the three compounds are Pauli paramagnets with essentially temperature-independent susceptibilities \[2\]. When the iron group elements are introduced as impurities into pure Th, a 1.36 K superconductor, Fe, Co and Ni are either negligibly soluble or little affect T c while Mn and Cr depress T c extremely rapidly \[3\]. T_hMn and ThCr are thought to be Kondo systems \[4\]; and Th7Mn 3 and Th7Cr3, of course, do not form. In ThvFe3, ThvCo 3 and ThTNi 3 the iron group 3d-shells are certainly filled; and their role in the superconductivity would seem to be minor. In another set * Research supported by the National Science Foundation under grants DMR 80-10530 and DMR 82-03690. * Present address: Laboratory of Nuclear Studies, Cornell University, Ithaca, NY 14853, USA.
Copyright 2014 Elsevier B.V., All rights reserved.
ASJC Scopus subject areas
- Engineering (all)