New columnar Zn-phthalocyanine designed for electronic applications.

Columnar liquid crystals are composed of disk-shaped aromatic molecules surrounded by flexible side chains, where molecules self-assemble in columns and thereby form large surface-oriented domains. These systems are known for their good charge and exciton transport along the columns, with mobilities approaching those of aromatic single crystals. Such semiconducting materials are promising for devices applications, since the output efficiency can be tuned by properly aligning columns.

Luminescent columnar liquid crystals based on tristriazolotriazine.

Five discotic molecules comprising a tris[1,2,4]triazolo[1,3,5] triazine core were designed and synthesized to obtain luminescent and charge-transporting columnar liquid crystalline materials. With the exception of one compound containing terminal hydroxyl groups all compounds presented a wide thermal range and stable columnar liquid crystalline phase, characterized by differential scanning calorimetry, polarized optical microscopy, and X-ray diffraction (XRD) techniques. The phase formation appeared to be associated to some extent with interdigitation of the alkoxy and benzylalkoxy portion, as suggested by the XRD results.

trans-Diaqua-bis{1,3-bis-[5-(2-pyrid-yl)-2H-tetra-zol-2-yl]propane}zinc(II) bis-(perchlorate).

The Zn(II) ion in the title compound, [Zn(C(15)H(14)N(10))(H(2)O)(2)](ClO(4))(2), lies on a centre of symmetry. The distorted N(4)O(2) octa-hedral coordination environment around the Zn atom is composed of two 1,3-bis-[5-(2-pyrid-yl)-2H-tetra-zol-2-yl]propane ligands (L1) and two water mol-ecules, coordinated in trans positions. The ligand acts as a typical bidentate chelating ligand through one of its 2-pyridyl-2H-tetra-zole units, forming a five-membered Zn-N-C-C-N metallacycle with a small N-Zn-N bite angle [77.