Experimental and computational evidence of the intermolecular motifs in the crystal packing of luminescent pentacoordinated gallium(III) complexes

Dalton Trans. 2006 Nov 21:(43):5124-34. doi: 10.1039/b606895b. Epub 2006 Jul 17.

Abstract

This paper reports the synthesis, characterization, photophysical and structural properties of the homologous series of good emitting pentacoordinated GaQ'2L complexes 1-3, where Q' is 2-methyl-quinolin-8-olate and L is a phenolate substituted in para position with respect to the oxygen donor atom. A combined approach between the experimental structural analysis (i.e. the molecular fragments involved in intermolecular pi-pi interactions) and the computational study (i.e. the nature of the molecular orbitals residing therein) is discussed in order to compare the charge transport aptitude of complexes 1-3, in relation to the facing of their LUMO/LUMO, HOMO/HOMO and HOMO/LUMO arising from the molecular packing. The different phenolate ligands significantly change the packing characteristics of 1-3, with indirect effects on the electron hopping kinetics responsible for conduction in amorphous thin films. The observed preference for pyridyl-pyridyl stacking proves a faster electron conduction in comparison to hole conduction in the three complexes studied.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Computer Simulation*
  • Crystallization
  • Crystallography, X-Ray
  • Gallium / chemistry*
  • Luminescence
  • Models, Molecular
  • Molecular Conformation
  • Organometallic Compounds / chemical synthesis
  • Organometallic Compounds / chemistry*
  • Quantum Theory
  • Stereoisomerism

Substances

  • Organometallic Compounds
  • Gallium