INQUIMAE   12526
INSTITUTO DE QUIMICA, FISICA DE LOS MATERIALES, MEDIOAMBIENTE Y ENERGIA
Unidad Ejecutora - UE
artículos
Título:
Widely Differing Photochemical Behavior in Related Octahedral {Ru-NO}6 Compounds: Intramolecular Redox Isomerism of the Excited State Controlling the Photodelivery of NO
Autor/es:
ARIEL G. DE CANDIA; JUAN P. MARCOLONGO; ROBERTO ETCHENIQUE; LEONARDO D. SLEP
Revista:
INORGANIC CHEMISTRY
Editorial:
AMER CHEMICAL SOC
Referencias:
Año: 2010 vol. 49 p. 6925 - 6925
ISSN:
0020-1669
Resumen:
trans-[(NC)Ru(py)4(μ-CN)Ru(py)4(NO)]3+ (py = pyridine) is a stable species in aqueous solution. It displays an intense absorption in the visible region of the spectrum (λmax = 518 nm; εmax = 6100 M−1 cm−1), which turns this compound into a promising agent for the photodelivery of NO. The quantum yield for the photodelivery process resulting from irradiation with 455 nm visible light was found experimentally to be (0.06 ± 0.01) × 10−3 mol einstein−1, almost 3 orders of magnitude smaller than that in the closely related cis-[RuL(NH3)4(μ-pz)Ru(bpy)2(NO)]5+ species (L = NH3 or pyridine, pz = pyrazine, bpy = 2,2′-bipyridine; NO = 0.02−0.04 mol einstein−1 depending on L) and also much smaller than the one in the mononuclear compound trans-[ClRu(py)4(NO)]2+ (NO = (1.63 ± 0.04) × 10−3 mol einstein−1). DFT computations provide an electronic structure picture of the photoactive excited states that helps to understand this apparently abnormal behavior.