Cyclic (AlN)n Compounds as Precursors to Aluminum Nitride: Synthesis and Structure of ((CH3)2AlNH2)3 and the Planar Species ((t-C4H9)2AlNH2)3.

摘要

The crystal and molecular structures of organic compounds, ((CH3) (2 A1NH2)3 1 and ((t-C4 H9) 3 2, have been determined in connection with their investigation as possible precursors to aluminum nitride. Both compounds have an (A1N)3 ring-structure with distorted tetrahedral geometries for the ring A1 and N atoms. The distortion from tetrahedral geometry is most pronounced for the N atoms where the endocyclic A1-N-A1 bond angles average 125.3 for 1 and 134.2 for 2. The (A1N)3 ring in 1 is in a skew-boat conformation with no unusual intra- or intermolecular contacts. Compound 2 on the other hand exhibits an unprecedented planar (A1N)3 ring as required by a crystallographic three-fold symmetry axis. Keywords: Ceramic precursor, Aluminum nitride, Dialkylaluminum amides, Crystal structure, Molecular structure. (JS)