PMID- 19149466
OWN - NLM
STAT- MEDLINE
DCOM- 20100922
LR  - 20131121
IS  - 1520-510X (Electronic)
IS  - 0020-1669 (Linking)
VI  - 48
IP  - 4
DP  - 2009 Feb 16
TI  - Ligand-selective photodissociation from [Ru(bpy)(4AP)4]2+: a spectroscopic and 
      computational study.
PG  - 1469-81
LID - 10.1021/ic8015436 [doi]
AB  - The new complex [Ru(bpy)(4AP)(4)](2+) (1), where bpy = 2,2'-bipyridine and 4AP = 
      4-aminopyridine, undergoes selective photodissociation of two 4APs upon light 
      excitation of the metal-ligand-to-ligand charge-transfer (MLLCT) band at 510 nm. 
      The photoproducts of the reaction are mer-[Ru(bpy)(4AP)(3)(H(2)O)](2+) (2a) and 
      trans-(4AP)[Ru(bpy)(4AP)(2)(H(2)O)(2)](2+) (3a). Photodissociation occurs in two 
      consecutive steps with quantum yields of phi(1) = (6.1 +/- 1.0) x 10(-3) and 
      phi(2) = (1.7 +/- 0.1) x 10(-4), respectively. Complex 1 was characterized by 
      combined spectroscopic and theoretical techniques. EXAFS experiments at the Ru 
      K-edge (22 117 eV) of 1 in an aqueous solution gave a Ru-N distance of 2.09 +/- 
      0.01 A. Photoproducts were characterized by electronic spectroscopy, 1D and 2D 
      NMR, and mass spectrometry. Singlet and triplet excited states of 1 were studied 
      by density functional theory (DFT) and time-dependent DFT for characterizing the 
      optical properties of the complex. In the singlet state, (1)MC (metal-centered) 
      dissociative states lie 0.65 eV above the main (1)MLLCT transition in the visible 
      region of the UV-vis absorption spectrum. In the triplet state, the energy 
      difference between these states is not reduced. However, potential energy curves 
      of singlet and triplet excited states of 1 along the Ru-N(axial 4AP) and 
      Ru-N(equatorial 4AP) stretching coordinates show that the release of the first 
      4AP may occur from the triplet state by mixing of (3)MLLCT and (3)MC dissociative 
      states. This mixing is favored when the Ru-N(equatorial 4AP) bond is elongated, 
      explaining the formation of the photoproduct 2a.
FAU - Salassa, Luca
AU  - Salassa L
AD  - Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry CV4 
      7AL, United Kingdom.
FAU - Garino, Claudio
AU  - Garino C
FAU - Salassa, Giovanni
AU  - Salassa G
FAU - Nervi, Carlo
AU  - Nervi C
FAU - Gobetto, Roberto
AU  - Gobetto R
FAU - Lamberti, Carlo
AU  - Lamberti C
FAU - Gianolio, Diego
AU  - Gianolio D
FAU - Bizzarri, Ranieri
AU  - Bizzarri R
FAU - Sadler, Peter J
AU  - Sadler PJ
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Inorg Chem
JT  - Inorganic chemistry
JID - 0366543
RN  - 0 (Ligands)
RN  - 0 (Organometallic Compounds)
RN  - 551W113ZEP (2,2'-Dipyridyl)
RN  - 7UI0TKC3U5 (Ruthenium)
SB  - IM
MH  - 2,2'-Dipyridyl/*chemistry
MH  - Ligands
MH  - Light
MH  - Models, Molecular
MH  - Organometallic Compounds/*radiation effects
MH  - *Photochemical Processes
MH  - Ruthenium/*chemistry
MH  - Spectrum Analysis
EDAT- 2009/01/20 09:00
MHDA- 2010/09/24 06:00
CRDT- 2009/01/20 09:00
PHST- 2009/01/20 09:00 [entrez]
PHST- 2009/01/20 09:00 [pubmed]
PHST- 2010/09/24 06:00 [medline]
AID - 10.1021/ic8015436 [pii]
AID - 10.1021/ic8015436 [doi]
PST - ppublish
SO  - Inorg Chem. 2009 Feb 16;48(4):1469-81. doi: 10.1021/ic8015436.