What is "arsenic trisulfide"

alt. (context inorganic compound English) The bright yellow sulfide of arsenic, As₂S₃, that occurs as the mineral orpiment, and has been used as a pigment n. (context inorganic compound English) The bright yellow sulfide of arsenic, As₂S₃, that occurs as the mineral orpiment, and has been used as a pigment

Arsenic trisulfide is the inorganic compound with the formula As S. It is a bright yellow solid that is insoluble in water. It also occurs as the mineral orpiment (Latin: auripigment), which has been used as a pigment called King's yellow. It is produced in the analysis of arsenic compounds. It is a group V/VI, intrinsic p-type semiconductor and exhibits photo-induced phase-change properties. The other principal arsenic sulfide is AsS, a red-orange solid known as the mineral realgar.