pH-Dependent spectroscopic and luminescent properties, and metal-ion recognition studies of Re(I) complexes containing 2-(2'-pyridyl)benzimidazole and 2-(2'-pyridyl)benzimidazolate.

A series of Re(I) complexes, [Re(CO)(3)Cl(HPB)] (1), [Re(CO)(3)(PB)H(2)O] (2), [Re(CO)(3)(NO(3))(PB-AuPPh(3))] (3), and [Re(CO)(3)(NO(3))(PB)Au(dppm-H)Au](2) (4) [HPB = 2-(2'-pyridyl)benzimidazole; dppm = 2,2'-bis(diphenylphosphinomethane)], have been synthesized and characterized by X-ray diffraction. Complex 1, which exhibits interesting pH-dependent spectroscopic and luminescent properties, was prepared by reacting Re(CO)(5)Cl with an equimolar amount of 2-(2'-pyridyl)benzimidazole. The imidazole unit in complex 1 can be deprotonated to form the imidazolate unit to give complex 2.

Organic dyes with remarkably high absorptivity; all solid-state dye sensitized solar cell and role of fluorine substitution.

A series of new organic D-pi-A dyes, A1, A2-H and A2-F, possessing a remarkably high absorption extinction coefficient of epsilon > 5.0 x 10(4) M(-1) cm(-1) at peak wavelength were synthesized, among which, A2-F having a key fluorine substitution attains excellent all solid-state DSSC performance, with optimized parameters of eta = 4.86%, J(SC) = 7.

Design and synthesis of trithiophene-bound excited-state intramolecular proton transfer dye: enhancement on the performance of bulk heterojunction solar cells.

In an aim to harvest UV-near-visible (360-440 nm) photons as well as to increase the morphology in the bulk heterojunction solar cells, we report herein the strategic design, synthesis, and characterization of a novel excited-state intramolecular proton-transfer dye, 3-hydroxy-2-(5-(5-(5-(3-hydroxy-4-oxo-4H-chromen-2-yl)thiophen-2-yl)thiophen-2-yl)thiophen-2-yl)-4H-chromen-4-one (FT), which bears two key functional groups, namely 3-hydroxychromone chromophore and trithiophene backbone and is then exploited into the blends of regioregular poly(3-hexylthiophene) (RR-P3HT) and phenyl-C(61)-butyric acid methyl ester (PCBM). FT acts as an excellent UV-near visible absorber, which then undergoes excited-state intramolecular proton transfer, giving rise to an orange-red proton-transfer emission that was reabsorbed by P3HT via a Forster type of energy transfer. Introduction of FT to P3HT/PCBM blend films also improves the morphology of phase separated structure, in particular, enhances the interaction of P3HT chains and the hole mobility.

Photoisomerization of a maleonitrile-type salen Schiff base and its application in fine-tuning infinite coordination polymers.

Strategically designed salen ligand 2,3-bis[4-(di-p-tolylamino)-2-hydroxybenzylideneamino]maleonitrile (1), which has pronounced excited-state charge-transfer properties, shows a previously unrecognized form of photoisomerization. On electronic excitation (denoted by an asterisk), 1Z*-->1E isomerization takes place by rotation about the C2--C3 bond, which takes on single-bond character due to the charge-transfer reaction. The isomerization takes place nonadiabatically from the excited-state (1Z) to the ground-state (1E) potential-energy surface in the singlet manifold; 1Z and 1E are neither thermally inconvertible at ambient temperature (25-30 degrees C), nor does photoinduced reverse 1E*-->1Z (or 1Z*) isomerization occur.

Fluorescent protein red Kaede chromophore; one-step, high-yield synthesis and potential application for solar cells.

The one-step condensation between the Green Fluorescence Protein (GFP) chromophore and 1H-imidazole-5-carbaldehyde catalyzed by ZnCl(2) proved to be a facile method to synthesize the red Kaede chromophore and its derivatives (1a-d, 2, and 3 > 70%), among which 1a then demonstrated its potential as a dye in solar cell, with a moderate conversion efficiency (eta) of 3.04%.

Neutral, panchromatic Ru(II) terpyridine sensitizers bearing pyridine pyrazolate chelates with superior DSSC performance.

A new series of neutral, panchromatic Ru(II) terpyridine sensitizers (PRT1-PRT4) exhibit much higher molar extinction coefficients at 400-550 nm and superior DSSC performance in terms of conversion efficiency (eta = 10.05 for PRT4) and stability.

Novel single-crystal-to-single-crystal anion exchange and self-assembly of luminescent d(10) metal (Cd(II), Zn(II), and Cu(I)) complexes containing C(3)-symmetrical ligands.

Ligands L1 and L2' (L1=N,N',N''-tris(4-pyridyl)trimesic amide, L2'=N,N',N''-tris(3-pyridinyl)-1,3,5-benzenetricarboxamide) belonging to an interesting family of tripyridyltriamides with C(3)-symmetry have been utilized to construct 3D porous or hydrogen-bonded frameworks. Through a novel single-crystal-to-single-crystal anion-exchange process, [Cd(L1)(2)(ClO(4))(2)](n) (1c) can be obtained from [Cd(L1)(2)Cl(2)](n) (1b) in the presence of ClO(4)(-) anions. This anion-exchange process is highly selective and only the substitution of Cl(-) by ClO(4)(-) or PF(6)(-) could be realized; Cl(-) was found not to be substituted by BPh(4)(-).

Crystal-engineering studies of coordination polymers and a molecular-looped complex containing dipyridyl-amide ligands.

We report herein crystal-engineering studies of coordination polymers and a molecular-looped complex containing two dipyridyl-amide ligands, 1,3-bis-pyridin-4-ylmethyl urea (L1) and N,N'-bis-4-methylpyridyl oxalamide (L2). The reaction of Cd(OAc)2 with L1 gives rise to [Cd(OAc)2(L1)]n (1), a 1-D chain through coordination to two L1 and two acetate ligands, and then the axial coordination to one urea's carbonyl group through the third L1 ligand leads 1 to form "a dimer of 1-D chains". With a slight change in the structural backbone from L1 to L2, the reaction of L2 with Cd(OAc)2 gives [Cd(OAc)2(L2)(H2O)]n (2), a 1-D chain structure.