Infrared transmission of chalcohalide glasses in the Ge-Se-Te-I system

► Infrared transmission spectra of some (Ge22Se14Te64)100−xIx glasses were studied. ► The increasing of iodine content enhanced the IR transmission. ► Purification of the raw elements decreased the absorption peaks. ► The annealing of glasses up to 423 K increased the IR transmission. ► Growth of hexagonal Te microcrystals at 473 K decreased the IR transmission.