title: Experimental and computational evidence of the intermolecular motifs in the crystal packing of luminescent pentacoordinated gallium(III) complexes.
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.
authors.affiliation: Centro di Eccellenza CEMIF.CAL-LASCAMM, CR-INSTM Unità della Calabria, Dipartimento di Chimica, Università della Calabria, I-87036, Arcavacata di Rende (CS), Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Crispini
authors.forename: Iolinda
authors.initials: I
authors.lastname: Aiello
authors.forename: Massimo
authors.initials: M
authors.lastname: La Deda
authors.forename: Irene
authors.initials: I
authors.lastname: De Franco
authors.forename: Mario
authors.initials: M
authors.lastname: Amati
authors.forename: Francesco
authors.initials: F
authors.lastname: Lelj
authors.forename: Mauro
authors.initials: M
authors.lastname: Ghedini
mesh_terms: D003198:Computer Simulation; D003460:Crystallization; D018360:Crystallography, X-Ray; D005708:Gallium / Q000737:chemistry*; D049449:Luminescence; D008958:Models, Molecular; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D011789:Quantum Theory; D013237:Stereoisomerism
chemical_list: D009942:Organometallic Compounds; D005708:Gallium