The physical properties of glasses in the Ge30As10Se((60-x))Te(x) system with x = 25, 28, 30, and 35 at.% Te, the Ge(30)As(10)Se(30)Teo((30-y))I(y) system with y = 5, 10, 20, and 30 at.% I, the Ge30As10Se35Te(25-z)Iz system with z = 2, 6, 10, and 20 at. % I, and the [Ge30As10Se30Te30]((100-w))I-w system with w = 0, 5, 10, and 20 at,% I have been investigated. The changes in the glass transition temperature, density, coefficient of thermal expansion, hardness, and viscosity are attributed to the delocalized metallic bonding character of Te in the substitution of Te for Se in the Ge-As-Se-Te glass system and the network-terminating role of iodine in the substitution of I for Te in the Ge-As-Se-Te-I glass system, respectively.