Pressure effect on magnetic susceptibility of SmS in the “black” phase.

New experimental results on the pressure dependence of magnetic susceptibility χ of SmS in semiconducting phase are obtained with precise measurements of χ as a function of the hydrostatic pressure P up to 2 kbar at liquid nitrogen and room temperatures. A pronounced magnitude of the pressure effect is found to be positive in sign and strongly temperature dependent: the pressure derivatives of χ , d ln χ /d P , are 6.3 ± 0.5 and 14.2 ± 1 Mbar −1 at 300 and 78 K, respectively. The experimental results are supplemented by theoretical calculations of the volume dependent electronic structure of SmS and orbital magnetism of the band electronic states χ VV(band) . It was found that χ VV(band) value appeared to be strongly dependent on pressure, determining the main mechanism of the observed puzzling pressure effects in semiconducting SmS compound. [ABSTRACT FROM AUTHOR]