Novel compounds having a formula M.sup.1.sub.dM.sup.2.sub.eM.sup.3.sub.fCh.sub.g where M.sup.1 is a transition metal, a group III, group IV, or group V element, M.sup.2 is a group 13, group 14, or group 15 element, and M.sup.3 and Ch independently are group 15 or group 16 elements, and a method for making the same are disclosed. The compounds may have a tetrahedrite crystal structure. Also disclosed are novel compounds having a formula A.sup.1.sub.3MCh.sup.a.sub.4 where A.sup.1, is a transition metal, M is a transition metal, a group 14 element, a group 15 element or a combination thereof, and Ch.sup.a is a group 16 element. Also disclosed are methods of making and using the compounds. The compounds may form part of a device. Some devices may comprise both a tetrahedrite and a A.sup.1.sub.3MCh.sup.a.sub.4 compound. Some devices may have an electrical output, for example a photovoltaic device, such as a thin film solar cell.
ACKNOWLEDGMENT OF GOVERNMENT SUPPORT
 This invention was made with government support under Contract No. DE-AC36-08GO28308 awarded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. The United States government has certain rights in the invention.