Cadmium arsenide (Cd₃As₂) is a crystalline semiconductor with a tetragonal structure in the II-V family. It is a narrow gap semiconductor with an energy gap of 0.14 eV. The electron mobility is very large at ambient temperature. General Name, Symbol, Number Cadmium, Cd, 48 Chemical series Transition metals Group, Period, Block 12, 5, d Density, Hardness 8650 kg/m3, 2 Appearance Silvery gray metallic Atomic properties Atomic weight 112. ... General Name, Symbol, Number arsenic, As, 33 Series metalloids Group, Period, Block 15 (VA), 4, p Density, Hardness 5727 kg/m3, 3. ... Quartz crystal A crystal is a solid in which the constituent atoms, molecules, or ions are packed in a regularly ordered, repeating pattern extending in all three spatial dimensions. ... A semiconductor is a material which has an electrical conductance which is between that of an insulator and a conductor. ... In crystallography, the tetragonal crystal system is one of the 7 lattice point groups. ... eV may stand for: electronvolt eingetragener Verein, i. ... In physics, electron mobility (or simply, mobility), is used to describe the relation between drift velocity of electrons or holes in a solid material or electrons/ions in a gas, and an applied electric field. ...