Ab-initio calculations of transport, optical and dielectric properties of substituted Lizardite

Abstract

DFT calculations have successfully predicted substituted lizardites with spin-filter properties that could pave the way for the design of new materials. Ni-substituted lizardite, also known as Nepouite, demonstrates a structural and mechanical stability and a wide band-gap semiconductor nature. A detailed study on the thermoelectric and optical properties was performed. The stable structure of the above clay mineral has been performed to demonstrate its potential in future technological applications. The doping and the temperature dependencies of the electrical conductivity, electronic thermal conductivity, Seebeck coefficient and power factor have been detailed. The optical properties involve a detailed calculation of the dielectric function, absorption coefficient, refractive index, reflectivity and loss function. A steep increase in the electrical conductivity and the power factor with carrier concentration are observed. However an increase in temperature tends to demonstrate a gradual decrease of the power factor. Electrical conductivity in Nepouite is found to be much higher than that of lizardite. The dielectric constant demonstrates a isotropic nature unlike lizardite. However a low reflectivity is maintained on substitution.