Order-disorder transition in silver-intercalated niobium disulfide compounds. II. Magnetic and electrical properties

The dc electrical conductivity, the Hall effect, the thermoelectric power, and the magnetic susceptibility of Ag-intercalated 2H-NbS₂ have been measured as a function of temperature for various Ag contents in Agₓ{NbS}₂$. The electrical resistivity exhibits a strong anomaly near T=124 K. The Hall and Seebeck coefficients only show weak anomalies at this temperature. These results are related to the structural changes occurring at the phase transition near T=124 K. The Hall and Seebeck coefficients have opposite signs for all compositions considered and point to a two-carrier-type conduction. The magnetic measurements show an increased filling of the Nb dz² band with higher Ag content and are in qualitative agreement with a rigid-band model for intercalation.