Magnetic and Transport Properties of Ba6Fe8S15 and BaFe2S3:  Magnetoresistance in a Spin-Glass-Like Fe(II) System

• Published in: Chemistry of materials Vol. 12; no. 11; pp. 3331 - 3336
• Main Authors: Gönen, Z. Serpil, Fournier, Patrick, Smolyaninova, Vera, Greene, Richard, Araujo-Moreira, Fernando M, Eichhorn, Bryan
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 20.11.2000
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Conductivity phenomena in semiconductors and insulators; Electronic transport in condensed matter; Exact sciences and technology; Galvanomagnetic and other magnetotransport effects; Magnetic properties and materials; Magnetically ordered materials: other intrinsic properties; Physics; Saturation moments and magnetic susceptibilities; Spin glasses; Inorganic compounds; Semiconductor materials; Magnetization; Barium sulfides; Iron sulfides; Ternary compounds; Transition element compounds; Experimental study; Magnetoresistance; Short range correlation; Magnetic susceptibility
• ISSN: 0897-4756; 1520-5002
• DOI: 10.1021/cm0000346

The magnetic and transport properties of the Hong and Steinfink 1-dimensional barium iron sulfide phases BaFe2S3 and Ba6Fe8S15 were studied. The valence precise BaFe2S3 phase (Fe2+) is semiconducting with a nonmagnetic ground state due to strong intrachain antiferromagnetic coupling. However, short-range magnetic correlations and spin-glass-like behavior are found below 25 K, which gives rise to a magnetoresistive effect of 10% at 9 T. BaFe2S3 is a rare example of a magnetoresistive ternary sulfide. The mixed valent Ba6Fe8S15 phase (Fe2.25+) is also a semiconductor with a nonmagnetic ground state. Ba6Fe8S15 shows similar spin-glass-like behavior but at a lower temperature (T f = 15 K). Comparisons with other tetrahedrally coordinated iron sulfide phases and possible origins of the short-range magnetic correlations are discussed.