spectroscopy. These newly synthesized isomeric complexes have been used as the sensitizers as well as co-sensitizers with state-of-the-art N719 dye in dye sensitized solar cells (DSSCs). Amongst all threeisomeric complexes, the DSSC assembly fabricated with 4-Py-Zn/N719 dye shown best performance with an overall photon-to-current conversion efficiency (PCE) of 6.52% with IPCE of 44%. The obtained co-sensitization
Novel 4-pyridinamine derivatives having the formula ##STR1## [where R.sup.1 and R.sup.2 are aryl or heteroaryl (optionally linked together by a lower alkylene bridge) or one of R.sup.1 and R.sup.2 is aryl or heteroaryl and the other of R.sup.1 and R.sup.2 is lower alkyl or ar(lower)alkyl, R.sup.3 and R.sup.4 are each hydrogen or lower alkyl and n is 0 or 1] and their non-toxic acid addition salts are described. They show CNS activity and may be used as antidepressant drugs. Some also show stimulant activity. Novel intermediates having the formula ##STR2## are also described.
The reaction of 2-(2'-pyridylmethyleneamino)pyridine (L-1)/3-(2'-pyridylmethyleneamino)pyridine (L-2)/4-(2'-pyridylmethyleneamino)pyridine (L-3) with CuX (X = Cl, Br, I) and triphenylphosphine (PPh3) affords complexes of composition [Cu(L)(PPh3)X]. These are characterized by microanalytical data and spectroscopic studies (IR, UV-Vis, H-1 NMR). The single crystal X-ray structure determines the distorted tetrahedral geometry about Cu(I) in case of [Cu(L-2)(PPh3)I]. Cyclic voltammogram shows Cu(II)/Cu(I) couple at 0.5-0.6 V, in addition [Cu(L)(PPh3)I] shows iodide oxidation peak at 0.3 V. Redox couple negative to SCE may be assigned to the reduction of chelated diimine function. Electronic structure, spectra, emission properties and redox activities are explained by DFT calculations of optimized geometry of [Cu(L-2)(PPh3)X] and have been used to determine the composition and energy of the molecular levels. (C) 2012 Elsevier B.V. All rights reserved.
From mononuclear to polynuclear: copper and zinc complexes obtained from polypyridylamine ligands related to tris(2-pyridylmethyl)-amine (tmpa)
Copper(I)/(II) complexes and a zinc compound with polypyridylamine ligands (related to the tripodalligand tris(2-pyridylmethyl)amine, tmpa) were synthesized. Crystallographic characterization was possible for most of the complexes obtained. The different structures of the complexes allowed some insight into the basic understanding of the design of coordination polymers. Depending on ligand, solvent