Inter- and Intramolecular Quenching of Porphyrin Excited States by Quinones

AbstractPhotochromic materials have drawn growing attention because using light as a stimulus has been regarded as a convenient and environmental-friendly way to control properties of smart materials. While photoresponsive systems that are capable of showing multiple-state photochromism are attractive, the development of materials with such capabilities has remained a challenging task. Here we show that a benzo[b]phosphole thieno[3,2‑b]phosphole-containing alkynylgold(I) complex features multiple photoinduced color changes, in which the gold(I) metal center plays an important role in separating two photoactive units that leads to the suppression of intramolecular quenching processes of the excited states. More importantly, the exclusive photochemical reactivity of the thieno[3,2‑b]phosphole moiety of the gold(I) complex can be initiated upon photoirradiation of visible light. Stepwise photochromism of the gold(I) complex has been made possible, offering an effective strategy for the construction of multiple-state photochromic materials with multiple photocontrolled states to enhance the storage capacity of potential optical memory devices.

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CIDEP Effects of Intramolecular Quenching of Singlet and Triplet Excited States by Nitroxide Radicals in Oligopeptides: A Potentially Useful New Method for Investigating Peptide Secondary Structures in Solution

Chemistry - A European Journal ◽

10.1002/1521-3765(20000804)6:15<2775::aid-chem2775>3.0.co;2-1 ◽

2000 ◽

Vol 6 (15) ◽

pp. 2775-2782 ◽

Cited By ~ 21

Author(s):

Carlo Corvaja ◽

Elena Sartori ◽

Antonio Toffoletti ◽

Fernando Formaggio ◽

Marco Crisma ◽

...

Keyword(s):

Excited States ◽

Secondary Structures ◽

New Method ◽

Nitroxide Radicals ◽

Intramolecular Quenching ◽

Triplet Excited States

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The search for fluorescence and the study of radiationless transitions of electronic excited states of NH3+

Canadian Journal of Chemistry ◽

10.1139/v85-238 ◽

1985 ◽

Vol 63 (7) ◽

pp. 1386-1389 ◽

Cited By ~ 14

Author(s):

Gérald Dujardin ◽

Sydney Leach

Keyword(s):

Quantum Yield ◽

Potential Energy ◽

Excited States ◽

Potential Energy Surfaces ◽

Dissociation Limit ◽

Experimental Conditions ◽

Electronic Excited States ◽

Intramolecular Quenching ◽

Upper Limits ◽

Energy Surfaces

Photoion – fluorescence photon coincidence experiments were carried out in order to detect the fluorescence of NH3+ which is expected to occur from that part of its Ã electronic state that lies below the lowest dissociation limit. Hel and Nel sources were used to produce the ions. No NH3+ fluorescence was detected and upper limits for its quantum yield under our experimental conditions are given. We show that the lifetime of the Ã state is probably very long, making it difficult to observe fluorescence. Furthermore, we argue that the molecular parameters and potential energy surfaces of the Ã and [Formula: see text] states are such that resonance limit nonradiative coupling to high rovibrational levels of the [Formula: see text] state could be an efficient process for apparent intramolecular quenching of NH3+Ã state fluorescence.

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Dinuclear Ruthenium(II) Polypyridyl Complexes Containing Large, Redox-Active, Aromatic Bridging Ligands: Synthesis, Characterization, and Intramolecular Quenching of MLCT Excited States

Inorganic Chemistry ◽

10.1021/ic011028u ◽

2002 ◽

Vol 41 (9) ◽

pp. 2471-2476 ◽

Cited By ~ 115

Author(s):

Mahn-Jong Kim ◽

Rama Konduri ◽

Hongwei Ye ◽

Frederick M. MacDonnell ◽

Fausto Puntoriero ◽

...

Keyword(s):

Excited States ◽

Bridging Ligands ◽

Polypyridyl Complexes ◽

Intramolecular Quenching ◽

Redox Active ◽

Dinuclear Ruthenium

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Vuv Spectra Y to Mo

International Astronomical Union Colloquium ◽

10.1017/s0252921100107808 ◽

1988 ◽

Vol 102 ◽

pp. 239

Author(s):

M.S.Z. Chaghtai

Keyword(s):

Excited States ◽

Spectral Analyses ◽

Vuv Spectra

Using R.D. Cowan’s computations (1979) and parametric calculations of Meinders et al (1982), old analyses are thoroughly revised and extended at Aligarh, of Zr III by Khan et al (1981), of Nb IV by Shujauddin et Chaghtai (1985), of Mo V by Tauheed at al (1985). Cabeza et al (1986) confirmed the last one largely.Extensive studies have been reported of the 1–e spectra, Zr IV (Rahimullah et al 1980; Acquista and Reader 1980), Nb V (Shujauddin et al 1982; Kagan et al 1981) and Mo VI (Edlén et al 1985). Some interacting 4p54d2levels of these spectra have been reported from our laboratory, also.Detailed spectral analyses of transitions between excited states have furnished complete energy values for J ≠ 1 levels of these spectra during 1970s and 80s. Shujauddin et al (1982) have worked out Nb VI and Tauheed et al (1984) Mo VII from our lab, while Khan et al (1981) share the work on Zr V with Reader and Acquista (1979).

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