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Triplet‐triplet annihilation upconversion
Nachrichten aus der ChemieAbstractTriplet‐triplet annihilation upconversion can generate UV light from visible light LEDs and visible light from infrared. Producing higher‐energy photons at the location where they are needed is useful: some functional groups do not tolerate irradation with UV light, and visible light does not penetrate cells and polymers as deep as infrared ...
Line Næsborg, Rubaishan Jeyaseelan
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Triplet-Triplet Spectroscopy of Polyacenes
The Journal of Chemical Physics, 1972Complete triplet—triplet absorption spectra (2000–10000 Å) were measured in alcoholic solution at 113°K with naphthalene, anthracene, tetracene, and a few methylated derivatives. Several new bands were observed. Calculations of the higher ππ* triplet states energies with the LCAO—MO—SCF Pariser—Parr—Pople method were improved by the use of large ...
Y. H. Meyer, R. Astier, J. M. Leclercq
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Semiempirical calculations of singlet-triplet and triplet-triplet transitions
Theoretica Chimica Acta, 1969Semiempirical calculations of the PPP-type with optimum values of parameters (γ μμ=8.2 eV, β c=−2.5 eV) reproduce fairly well the singlet-triplet (S-T) and triplet-triplet (T-T) excitation energies and oscillator strengths with conjugated hydrocarbons of various structural types. The usefulness of this parametrization is shown with anthracene. Moreover,
J. Pancíř, R. Zahradník
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Triplet—Triplet Transitions in Naphthalene
The Journal of Chemical Physics, 1967A Pariser—Parr type CI calculation has been made for the triplet—triplet transitions of naphthalene. All configurations singly and doubly excited with respect to the lowest triplet state and with an energy relative to the lowest triplet not exceeding 7.5 eV have been taken into account. The results have taken away the discrepancy between
R. L. de Groot, G. J. Hoytink
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Benchmarking triplet–triplet annihilation photon upconversion schemes
Physical Chemistry Chemical Physics, 2018TD-DFT benchmark with and without the Tamm–Dancoff approximation of sensitizer/annihilator pairs relevant for triplet–triplet annihilation photon upconversion.
Anders S. Gertsen +2 more
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[C70] Fullerene-sensitized triplet–triplet annihilation upconversion
Chemical Communications, 2013We herein report the first instance of using pristine C70 as a heavy-atom free organic sensitizer for efficient triplet-triplet annihilation upconversion (UC) for both green-to-blue and red-to-green UC using 9,10-bis(phenylethynyl)anthracene and perylene as acceptors, respectively. C70 achieved quantum yields of 8% and 0.8% for green-to-blue and red-to-
Kyle, Moor +3 more
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Triplet-triplet absorption in benzene
Tetrahedron, 1970Abstract Triplet-triplet absorption in benzene has been calculated semiempirically by considering all single excitations and a limited number of double excitations. The numerical results show several allowed 38Bu → 3E2g transitions of varying intensity.
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Detecting triplet locking by triplet synchronization indices
Physical Review E, 2013We discuss the effect of triplet synchrony in oscillatory networks. In this state the phases and the frequencies of three coupled oscillators fulfill the conditions of a triplet locking, whereas every pair of systems remains asynchronous. We suggest an easy to compute measure, a triplet synchronization index, which can be used to detect such states ...
Kralemann, Björn +2 more
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Triplet-triplet absorption and energy transfer from high triplet states
Spectrochimica Acta Part A: Molecular Spectroscopy, 1971Abstract A simple method for determining of triplet-triplet extinction coefficients which is based on the non-linear effect in transitions between three levels of Jablonsky diagram has been suggested. Triplet concentrations were obtained from the expression N T st = C 0 (1 - τ r /τ d ), where τ r and τ d are the rise time and ...
M.V. Alfimov +3 more
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Triplet–triplet Annihilation Up-conversion
2014In this chapter we outline how solar cells may be enhanced by photochemical up-conversion brought about by triplet–triplet annihilation. We begin by introducing the photon–ratchet model of a quantum photovoltaic energy convertor. The Shockley–Queisser limit is determined, and the model is extended to include a generalized photon up-convertor.
Timothy W. Schmidt, Murad J. Y. Tayebjee
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