Molecular structure of the azidoalane [Me2N(CH2)3]AltBu(N3).: X-ray structural determination and ab initio calculations

A single crystal of the azidoalane [Me2N(CH2)(3)]AltBu(N-3) (1a), grown in a capillary using a miniature zone melting procedure, was investigated by X-ray analysis. Compound 1a (C9H21AlN4) is a monomeric species in the solid state, which crystallizes in the monoclinic space group P2(1) with a = 6.8560(14) Angstrom, b = 12.251(3) Angstrom, c = 7.786(2) Angstrom, beta = 108.51(3)degrees and Z = 2. The results of the X-ray structural determination are compared with thr calculated structure of la (HF/6-31G(d) and B3LYP/6-31G(d) level of theory). Whereas the overall agreement between the measured acid calculated structure is good, the Al-N donor-bond length differs by 11 and 12 pm at the HF and B3LYP level, respectively. To evaluate the effects of a polar environment on the molecular structure of la self-consistent reaction field (SCRF) calculations at the HF and B3LYP level with the 6-31G(d) basis set were performed. (C) 2000 Elsevier Science B.V. All rights reserved.