Resistance Anomaly in Quasi-One-Dimensional Sulfide BaNbS3+δ

✍ Scribed by Norihito Kijima; Kenichi Morie; Susumu Chikazawa; Hironori Nishihara; Shoichi Nagata

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 195 KB
• Volume: 142
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1998.7985

✦ Synopsis

Single-phase specimens of hexagonal BaNbS 3؉ (2.934 43 ؉ 4 43.06) have been successfully prepared by the sulfurization method using CS 2 . The lattice constants, a and c, are less sensitive to the value of in the region of ؊0.074 4 4 40.06. BaNbS 2.93 indicates a semiconductor-to-semiconductor gradual transition around 100 K. On the other hand, BaNbS 3؉ (2.964 43 ؉ 4 43.06) shows hump-shaped anomalous behaviors in the resistivity. Although the anomalies in the electrical resistivity have been observed, all the samples have indicated no anomaly in their magnetic susceptibility. The magnetic susceptibilities are nearly temperature independent with extremely small Curie-like behavior at low temperatures. BaNbS 2.98 does not undergo a structural phase transition and there is no change in symmetry down to 80 K, above which the hump-shaped anomaly is clearly found. The relationship in the resistance anomaly between BaNbS 3؉ and BaVS 3 seems to be significant and to have an important role in clarifying the mechanism of these anomalies.