Dynamic Processes in the Lowest-Excited 3MLCT States of [M(L)3-x (L')x]2+ (L,L' = diimine; M = Ru,Os)

Abstract A clear understanding of the lowest-excited 3MLCT states of [Ru(bpy)3]2+ and related systems in crystalline hosts of well-defined symmetry is outlined, based on a range of incisive experiments such as Zeeman, Stark, line narrowing and spectral hole-burning measurements. The lowest-excited 3MLCT states of ruthenium complexes are localised. The intramolecular excitation energy transfer can be relatively slow (≈ 10 ns). In the [Os(bpy)3]2+ complex analogous excitations are well described as coherent intramolecular excitons. Cases are found in which the small effect associated with selective deuteration leads to exciton localisation. The influence of nanoheterogeneity in solutions and glasses gives rise to a substantial inequivalence of the ligands, invariably leading to localization.

[1]  E. Krausz,et al.  Site‐selective and Stark spectroscopy of the series [Os(2,2’‐bipyridine)3−x(2,2’‐bipyridine‐d8)x]2+ (x=0–3) in single‐crystal [Ru(2,2’‐bipyridine)3](PF6)2. Localization of an intramolecular triplet metal‐to‐ligand charge transfer exciton by partial deuteration , 1995 .

[2]  Hans Riesen,et al.  Intramolecular energy transfer and excitation coupling in metal-to-ligand charge transfer (MLCT) excited states , 1995, Other Conferences.

[3]  E. Krausz,et al.  Crystal Structures of and Polarized Absorption-Spectroscopy in Racemic and Resolved [Ru(bpy)3] (ClO4)2 and [Zn(bpy)3] (ClO4)2Bpy=2,2'-Bipyridine , 1995 .

[4]  E. Krausz,et al.  Intramolecular transfer of3MLCT excitation energy in [Ru(bpy)3]2+ , 1994 .

[5]  E. Krausz,et al.  Localised3MLCT states of [Ru(bpy)3−x(phen)x]2+ (x=0 to 3) in racemic [Zn(bpy)3] (ClO4)2 , 1994 .

[6]  E. Krausz,et al.  Stark and Zeeman effects in the lowest excited states of [Zn(bpy)3](ClO4)2:Ru(II). Localized triplet metal-to-ligand charge transfer transitions , 1994 .

[7]  Hartmut Yersin,et al.  Electron Delocalization and Localization in Mixed-Ligand [Ru(LL)n(LL')3-n]2+ Complexes , 1994 .

[8]  G. Crosby,et al.  Nature of the emitting 3MLCT manifold of rhenium(I) (diimine) (CO)3Cl complexes , 1994 .

[9]  E. Krausz,et al.  Orientational dependences of the Zeeman effect in the lowest-excited states of [Zn(bpy)3](ClO4)2:Ru(II) and [Ru(bpy)3](PF6)2 , 1994 .

[10]  J. Harrowfield,et al.  The Crystal Structure of Tris(2,2'-bipyridine)ruthenium(II) Perchlorate , 1994 .

[11]  E. Krausz,et al.  Stark swept transient hole-burning and excited state dynamics in [Ru(bpy)3]2+ , 1994 .

[12]  Hartmut Yersin,et al.  Highly resolved emission of osmium-deuterated bipyridine compound [Os(bpy-h8)n(bpy-d8)3-n]2+ (n = 0-3): evidence for electronic delocalization , 1993 .

[13]  E. Krausz,et al.  Luminescence and excitation line narrowing of [Ru(2,2’‐bipyridine)3−x (2,2’‐bipyridine‐d8)x]2+ (x=0–3) in [Zn(2,2’‐bipyridine)3](CIO4)2. Unequivocal evidence for localized lowest‐excited states , 1993 .

[14]  E. Krausz,et al.  Stark-swept transient hole burning and resonant luminescence line narrowing in [Zn(2,2′-bipyridine)3](ClO4)2:Ru(II) , 1993 .

[15]  D. Braun,et al.  SPECTROSCOPIC PROPERTIES OF [Ru(bpy)2(bpz)]2+ , 1993 .

[16]  E. Krausz,et al.  Advances in High-Resolution Laser Spectroscopy of Coordination Compounds , 1993 .

[17]  H. Buergi,et al.  CRYSTAL AND MOLECULAR STRUCTURES OF RU(BPY)3(PF6)3 AND RU(BPY)3(PF6)2 AT 105 K , 1992 .

[18]  D. Braun,et al.  Site selective spectra of the lowest excited states of [Os(bpy)3]2+ in [Ru1-x Os x (bpy)3]X 2(X = PF6, AsF6, SbF6) , 1989 .

[19]  S. Yamauchi,et al.  Excited-state properties of a (2,2'-bipyridine)ruthenium(II) complex, [Ru(CN)4(bpy)]2-, a model of localized excitation , 1989 .

[20]  E. Krausz,et al.  Magnetic circularly polarized luminescence of the sharp zero-phonon lines in Ru(bpy)3(PF6)2 , 1988 .

[21]  E. Krausz,et al.  Zero-phonon lines and luminescence line narrowing in the series Ru(bpy-d8)x(bpy)3-x(PF6)2(x=1–3). Direct evidence for localization in the two lowest excited states , 1988 .

[22]  Vincenzo Balzani,et al.  Ru(II) polypyridine complexes: photophysics, photochemistry, eletrochemistry, and chemiluminescence , 1988 .

[23]  L. Brus,et al.  Picosecond Raman scattering study of electron localization in the charge-transfer excited state of tris(bipyridine)ruthenium(II) , 1987 .

[24]  E. Krausz.  Zeeman effects in absorption and luminescence of the zero-phonon lines in Ru(bpy)3(PF6)2 , 1987 .

[25]  E. Rashba,et al.  Spectroscopy of Molecular Excitons , 1985 .

[26]  M. Maeder,et al.  Electronic spectroscopy of M(bpy)2+3 (M = Fe, Ru, Os), Cr(bpy)3+3 and related compounds , 1985 .

[27]  V. Balzani,et al.  Luminescence of ruthenium(II) tris chelate complexes containing the ligands 2,2'-bipyridine and 2,2'-biisoquinoline. Behavior of the Ru(bpy)2+ and Ru(bpy)22+ emitting units , 1985 .

[28]  N. Kitamura,et al.  Spectroscopic and electrochemical studies on ruthenium(II) complexes containing diazadiimine ligands , 1983 .

[29]  M. Wrighton,et al.  Raman spectroscopy of electronic excited organometallic complexes: a comparison of the metal to 2,2'-bipyridine charge-transfer state of fac-(2,2'-bipyridine)tricarbonylhalorhenium and tris(2,2'-bipyridine)ruthenium(II) , 1983 .

[30]  L. Yellowlees,et al.  Ligand-ligand inter-valence charge-transfer absorption in reduced ruthenium(II) bipyridine complexes , 1982 .

[31]  Kuppuswamy Kalyanasundaram,et al.  Photophysics, photochemistry and solar energy conversion with tris(bipyridyl)ruthenium(II) and its analogues , 1982 .

[32]  N. Kress,et al.  Vibrational spectroscopy of the electronically excited state. 5. Time-resolved resonance Raman study of tris(bipyridine)ruthenium(II) and related complexes. Definitive evidence for the "localized" MLCT state , 1981 .

[33]  C. Carlin,et al.  Multiple state emission and related phenomena in transition metal complexes , 1981 .

[34]  D. Rillema,et al.  Structure of tris(2,2′-bipyridyl)ruthenium(II) hexafluorophosphate, [Ru(bipy)3][PF6]2; X-ray crystallographic determination , 1979 .

[35]  P. Prasad,et al.  Quantitative tests of mixed crystal excition theory. I. Naphthalene monomer1B2u and 3B1u spectra , 1974 .

[36]  D. Craig.  Excitons in Molecular CrystalS , 1968 .