A single source precursor for depositing ternary I-III-VI₂ chalcopyrite materials useful as semiconductors. The single source precursor has the I-III-VI₂ stoichiometry "built into" a single precursor molecular structure which degrades on heating or pyrolysis to yield the desired I-III-VI₂ ternary chalcopyrite. The single source precursors effectively degrade to yield the ternary chalcopyrite at low temperature, e.g. below 500 C., and are useful to deposit thin film ternary chalcopyrite layers via a spray CVD technique. The ternary single source precursors according to the invention can be used to provide nanocrystallite structures useful as quantum dots. A method of making the ternary single source precursors is also provided.