Compounds of the Se-doped layered transition-metal sulfide series BaCo0.9Ni0.1S2-ySey (y≤0.4) were prepared and structural, magnetic, and electrical properties were investigated. These compounds exhibit the unusual first-order antiferromagnetic semiconductor to paramagnetic metal transition with decreasing temperature that was previously seen in the sulfur-deficient BaCo1-xNixS2-y series. This transition is associated with a major structural change. The previously unknown crystal structure of the low-temperature phase is reported. Electrical resistance and magnetic susceptibility measurements are used to construct the phase diagram for BaCo0.9Ni0.1S2-ySey. Doping with Se increases the insulator-metal transition temperature, but has very little effect on other properties since it substitutes for S only in the BaS layers.
|Original language||English (US)|
|Number of pages||8|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - Nov 15 2000|