Electrical Transport Properties of the Misfit Layer Compounds (SnS)1. 20TiS2 and (PbS)1.18TiS2

Abstract

(SnS)1.20TiS2 and (PbS)1.18TiS2 are misfit layer compounds, built of alternate double layers SnS (PbS), actually a slightly distorted {001} slice of rocksalt type SnS (PbS), and sandwiches TiS2, slightly distorted compared to those of 1T-TiS2. The electrical transport properties, measured on single crystals for the in-plane resistivity (rho-ab), the resistivity along c (rho-c) and Hall coefficient (R(H)) and on powder compacts for the Seebeck coefficient (alpha) are metallic like those of 1T-TiS2 intercalated with an electron donating species. The rho-ab versus temperature curves are non-linear from 4 to 300 K. R(H) and alpha are negative for both compounds. The Hall coefficients at 300 K correspond with 0.20 +/- 0.04 e/Ti for (SnS)1.20TiS2 and 0.43 +/- 0.09 e/Ti for (PbS)1.18TiS2. The Seebeck coefficients point to 0.2 - 0.4 e/Ti.