Photochemical Reductive Elimination of Nitrogen from Triazidogallium(III). Generation of Luminescent Gallium(I)

Azide complexes of Ga(III) have attracted con­ siderable attention in recent years owing to their importance as precursors for the formation of GaN [1-4] . Gallium nitride is a rather stable III-V semi­ conductor with interesting optical properties which can be utilized for optoelectronic applications in­ cluding blue light-emitting diodes and lasers [5 7]. The thermal decomposition of Ga(N3)3 seems to proceed according to the simple stoichiometry Ga(N3)3 —> GaN + 4N2 [4], In distinction of the thermal behavior the light sensitivity of Ga(N3)3 has not yet been studied. We explored this possibil­ ity in the present investigation which is based on our previous experience with azido complexes of other s° metals such as [Sn(N3)6]2~ and [Pb(N3)6]2~ [8]. Generally, s° complexes undergo photochemical re­ ductive eliminations which lead to the correspond­ ing s2 complexes [9-11]. These photoredox reac­ tions are induced by ligand-to-metal charge transfer (LMCT) excitation.