Patent ID: 8158033

Claim:
A compound comprising repeating units {M B (ER)(ER)} and {M A (ER)(ER)}, wherein each M A is Cu or Ag, each M B is In, Ga or Al, one or more M B is Al, each E is S, Se, or Te, wherein the compound has the empirical formula (Cu 1-x Ag x ) u (In 1-y-t Ga x Al t ) v (S 1-z Se z )R) w , wherein x is from 0 to 1, y is from 0 to 1 minus t, t is from 0.001 to 1, the sum of y plus t is from 0.001 to 1, z is from 0 to 1, u is from 0.5 to 1.5, v is from 0.5 to 1.5, w is from 2 to 6, and R represents R groups, of which there are w in number, which are independently selected from alkyl, aryl, heteroaryl, alkenyl, amido, silyl, and inorganic and organic ligands.