[5‐(p‐alkoxy)phenyl‐10, 15, 20‐tri‐phenyl] porphyrin and their rare earth complex liquid crystalline

Abstract

Three series of porphyrin liquid crystalline compounds, [5‐(p‐alkoxy)phenyl‐10, 15, 20‐tri‐phenyl] porphyrin and their rare earth complexes (Tb (III), Dy (III), Er (III), Yb (III)), with a hexagonal columnar discotic columnar(Colh) phase have been synthesized. These compounds were characterized by elemental analysis, molar conductances, UV‐visible spectra, infrared spectra, luminescence spectra, and cyclic voltammetry. These compounds exhibit more than one mesophases, which transition points of temperature change from −33.6 to 16.0 °C, and transition points of temperature for isotropic liquid also increase from 4.9 to 38.2 °C, with increasing chain length. Their surface photovoltage (SPV) response have also been investigated by the means of surface photovoltage spectroscopy (SPS) and field‐induced surface photovoltage spectroscopy (EFISPS). It was found that their SPV bands are analogous with the UV‐visible absorption spectra and derived from the same transition. Copyright © 2007 John Wiley & Sons, Ltd.

Synthesis, structure, and surface photovoltage properties of a series of novel d7–d10 metal complexes with pincer N-heterocycle ligands

“…2,4-bis(3,5-dimethyl-1H-pyrazol-1-yl)-6-diethylamino-1,3,5-triazine, are not observed. [24][25][26][27][28][29][30][31][32] In order to further extend the structural variety and explore the surface photoelectron behaviors of the complexes, here, we firstly report the synthesis, structure, spectra and surface photovoltage properties of the five novel transition metalorganic complexes, namely Cu(bpz*eaT)(SCN) 2 (1), Ni(bpz*eaT) (SCN) 2 (2), Co(bpz*eaT)((SCN) 2 (3), [Ni(bpz*eaT)(N 3 ) 2 ]?H 2 O (4) and Co(bpz*eaT)(N 3 ) 2 (5).…”

Effect of Magnetic and Electric Field on the Orientation of Rare-Earth-Containing Nematics

“…Rare-earth ions have high coordination numbers (from 6 to 12), which do not favor the formation of an anisometric (calamitic) geometry of a complex required to generate a liquid-crystal state. Specific demands are, therefore, placed on the structure of a coordination polyhedron and the ligands that form the geometry of such a complex. , In our previous works, we characterized coordination compounds that included Schiff bases, , β-enamine ketones, β-diketones, − bis­(benzimidazolyl)­pyridines, , phthalocyanines, , porphyrins, , and crown ethers. , All of these complexes, however, exhibit only a smectic mesomorphism. Introducing lanthanide­(III) ions into an LC molecule results in a high viscosity of smectic or discotic mesophases due to strong intermolecular interactions.…”

Construction of a 2D Co(II) Coordination Polymer with (4,4)-Connected Topology: Synthesis, Crystal Structure, and Surface Photo-electric Property

“…36,37 SPS not only relates to the electron transition process caused by light absorption, but reflects the properties of separation and transition of photogenerated charges directly, so it is utilized to study the electron behaviors of the solid surface and interface. 38,39 Following the above consideration and our ongoing work in this field, 33,34,40,41 we herein present the synthesis and structure of the compound [Co(BTA) 2 (H 2 O) 2 ] n (1) (Scheme 1), which has been structurally characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and its surface photovoltage spectroscopy (SPS) property.…”