The main objective of the project is to obtain original data describing electrical and dielectric properties of selected new glasses based on heavy metal oxides and/or chalcogenides, to detect mechanisms affecting their electrical conductivity and to describe the relationship between transport properties and optical properties. Measurement of transport properties will provide a feedback for adjusting the composition of starting mixture and conditions of glass preparation resulting in increased homogeneity of the obtained material and reduced concentration of impurities. We will use the prepared samples of special glasses transmitting infrared radiation to: investigate their electrical and dielectric properties; determine diffusion coefficients of individual components in selected systems – diffusion parameters will be correlated with electrical properties and will help to clarify the mechanism of electrical conductivity of investigated glass; investigate the effect of impurities on measured properties; determine correlations between chemical composition, conditions during the preparation of glasses and physico-chemical properties of prepared glasses.