Thermal and electrical properties of rare earth based chalcogenide compounds R2X3 (R=Dy or Tb and X=S or Se)

Electronic and thermal properties of rare-earth chalcogenide compounds R2X3 (R = Dy/Tb and X = S/Se ) are investigated using Density Functional Theory. The effective mass, deformation potential and elastic constants are calculated. The rare-earth chalcogenide compounds are dynamically stable. The lattice thermal conductivity for these compounds is calculated using slack model. The lowest value of kl 4.5W/mK is obtained for Tb2Se3 This low thermal conductivity of these compounds can have several application in various fields like thermoelectric, thermal insulation and phononics.