Electronic Structure of Iron Substituted Lithium Intercalated TaS₂

Abstract

We have used the 57Fe Mossbauer effect to study the electronic spin configuration of Fe substituted in the layer compound LiuTaj.yFeyS 2 (0fxl; 0:y:50.1). The M6ssbauer effect results show that the Fe is localized and in Fe 2 + valence state but the electronic configuration depends on the lithium concentration. At room temperature the isomer shift of Fe 2 + increases from 0.56 mm/s for x = 0 (no Li) to 0.77 mm/s for x = .86 (at y = 0.05). The isomer shift results reflect the changes in the electronic configuration of the host from Ta 4 +(5d') to Ta 3 +(5d 2 ) and an increase in ionicity as the lithium content increases from 0 to 1.

Stabilization of antiferromagnetism in 1T-Fe$_{0.05}$TaS$_2$

“…The first candidate is Fe. In TaS 2 , Fe is usually localized and enters as Fe 2+ [28][29][30]. Thus, the spin-only effective moment due to Fe 2+ is 4.90µ B /Fe or 0.25µ B /f.u., which is smaller than the experimentally determined value of 0.865µ B /f.u.…”