Synthesis, Crystal Structure and Spectral Characterization, of a New Phase of Tris(phthalocyaninato)dibismuth(III), Bi2(Pc)3

Abstract

Direct-template synthesis and purification of a new phase of the triple-decker bismuth(III) phthalocyanine Bi2(Pc)3, prepared from bismuth acetate and phthalonitrile, are described. X-ray analysis shows a triple-decker molecular structure involving three phthalocyanine rings and two bismuth atoms that are 3.838(9) Å apart. The coordination polyhedron is a distorted square anti-prism. The average distances between the bismuth(III) and the isoindolic nitrogens are 2.336 Å and 2.726 Å, respectively, for the external saucer-shape ring and the more planar inner ring. The intramolecular distance between two neighbouring 4Niso mean-planes is 3.17 Å, the inner Pc ring being rotated by 38.3° with respect to the peripheral ones. The shortest intermolecular distance between two carbon atoms in the crystal packing is 3.284 Å. This black phase is a regular stack of phthalocyanine rings that have their π system all overlapping. UV/Visible and FT-IR spectra are discussed in relation to the molecular structure and fully characterize this triple-decker compound.