Search results for "Polypyridine complex"
showing 6 items of 6 documents
Polychromatic femtosecond fluorescence studies of metal–polypyridine complexes in solution
2011
Femtosecond-resolved broadband fluorescence studies are reported for[ M(bpy)(3)](2+) (M = Fe, Ru), RuN3 and RuN719 complexes in solution. We investigated the pump wavelength dependence of the fluorescence of aqueous [ Fe(bpy)(3)](2+) and the solvent and ligand dependence of the fluorescence of Ru-complexes excited at 400 nm. For all complexes, the (MLCT)-M-1 fluorescence appears at zero time delay with a mirror-like image with respect to the absorption. It decays in <= 30-45 fs due to intersystem crossing to the (MLCT)-M-3 states, but a longer lived component of similar to 190 fs additionally shows up in RuN719 and RuN3. No solvent effects are detected. The very early dynamics are character…
BODIPY-phosphane as a versatile tool for easy access to new metal-based theranostics
2012
A new BODIPY-phosphane was synthesized and proved to be a versatile tool for imaging organometallic complexes. It also led to easy access to a new family of theranostics, featuring gold, ruthenium and osmium complexes. The compounds' cytotoxicity was tested on cancer cells, and their cell uptake was followed by fluorescence microscopy in vitro.
A Bis(tridentate)cobalt Polypyridine Complex as Mediator in Dye‐Sensitized Solar Cells
2015
Dye-sensitized solar cells equipped with cationic and neutral RuII-based sensitizers [Ru(ddpd){tpy(COOH)3}]2+ [12+; ddpd = N,N′-dimethyl-N,N′-di(pyridin-2-yl)pyridin-2,6-diamine, tpy(COOH)3 = 2,2″6′,2″-terpyridine-4,4′,4″-tricarboxylic acid] and [Ru(ddpd){tpy(COOH)(COO)2}] (2) with and without the coadsorbent chenodeoxycholic acid were constructed with I3–/I– or the CoIII/II-based redox mediators [Co(bpy)3]3+/2+ (33+/2+; bpy = 2,2′-bipyridine) and [Co(ddpd)2]3+/2+ (43+/2+) in the presence of LiClO4 and 4-tert-butylpyridine. The best photovoltaic performance was achieved by using the 43+/2+ shuttle and the neutral sensitizer 2 without coadsorbent. The higher short-circuit photocurrent densit…
A heteroleptic bis(tridentate)ruthenium(II) polypyridine complex with improved photophysical properties and integrated functionalizability.
2010
The synthesis and photophysical properties of a ruthenium(II) complex bearing an electron-accepting 2,2';6',2''-terpyridine ligand and an electron-donating N,N'-dimethyl-N,N'-dipyridin-2-ylpyridine-2,6-diamine (ddpd) ligand are presented. The heteroleptic complex is easily prepared isomerically pure and features intense low-energy metal-to-ligand charge-transfer (MLCT) absorption bands and intense room temperature (3)MLCT emission with a long (3)MLCT lifetime. The favorable photophysical properties are due to the strong ligand field imposed by the ddpd ligand.
Understanding the Excited State Behavior of Cyclometalated Bis(tridentate)ruthenium(II) Complexes: A Combined Experimental and Theoretical Study
2015
The synthesis and characterization of the donor-acceptor substituted cyclometalated ruthenium(II) polypyridine complex isomers [Ru(dpb-NHCOMe)(tpy-COOEt)](PF6) 1(PF6) and [Ru(dpb-COOEt)(tpy-NHCOMe)](PF6) 2(PF6) (dpbH = 1,3-dipyridin-2-ylbenzene, tpy = 2,2';6,2"-terpyridine) with inverted functional group pattern are described. A combination of resonance Raman spectroscopic and computational techniques shows that all intense visible range absorption bands arise from mixed Ru → tpy/Ru → dpb metal-to-ligand charge transfer (MLCT) excitations. 2(PF6) is weakly phosphorescent at room temperature in fluid solution and strongly emissive at 77 K in solid butyronitrile matrix, which is typical for r…
Iridium(III) Complexes with Phenyl-tetrazoles as Cyclometalating Ligands
2014
Ir(II) cationic complexes with cyclometalating tetrazolate ligands were prepared for the first time, following a two-step strategy based on (i) a silver-assisted cyclometalation reaction of a tetrazole derivative with IrCl3 affording a bis-cyclometalated solvato-complex P ([Ir(ptrz)(2)(CH3CN)(2)](+), Hptrz = 2-methyl-5-phenyl-2H-tetrazole); (ii) a substitution reaction with five neutral ancillary ligands to get [Ir(ptrz)(2)L](+), with L = 2,2'-bypiridine (1), 4,4'-di-tert-butyl-2,2'-bipyridine (2), 1,10-phenanthroline (3), and 2-(1-phenyl-1H-1,2,3-triazol-4-yl)pyridine (4), and [Ir(ptrz)(2)L-2](+), with L = tertbutyl isocyanide (5). X-ray crystal structures of P, 2, and 3 were solved. Elect…