1. |
Spectra of Oligothiophenes with Limited Number of 3-Alkyl-Substituents: Influence of Aggregation |
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Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals,
Volume 218,
Issue 1,
1992,
Page 1-5
E.E. Havinga,
I. Rotte,
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摘要:
Absorption and emission spectra of the title oligothiophenes, both in chloroform solution and as solid (or in PMMA ss), are given. Evidence is found for the simultaneous existence of various conformers that differ markedly in their conjugation lengths.
ISSN:1058-725X
DOI:10.1080/10587259208047006
出版商:Taylor & Francis Group
年代:1992
数据来源: Taylor
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2. |
Intermolecular and Intramolecular Radiationless Processes in p-Terphenyl and Benzoic-Acid Single Crystals Doped with Tetra-Cene or Pentacene |
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Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals,
Volume 218,
Issue 1,
1992,
Page 7-12
Carola Kryschi,
Arnd Krüger,
Birgit Wagner,
Wolfgang Gorgas,
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摘要:
Singlet excitation energy transfer processes and inter-system crossing in the mixed crystalline systems, p-terphenyl: :tetracene, p-terphenyl:pentacene and benzoic acid:pentacene were investigated in the temperature range 2 - 300 K using stationary fluorescence spectroscopy.
ISSN:1058-725X
DOI:10.1080/10587259208047007
出版商:Taylor & Francis Group
年代:1992
数据来源: Taylor
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3. |
Optical Absorption of Molecular Chains: Influence of Conformational Disorder |
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Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals,
Volume 218,
Issue 1,
1992,
Page 13-18
V.I. Yudson,
P. Reineker,
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摘要:
The optical absorption line shape of a polymeric chain under the influence of conformational disorder is investigated. In the model consecutive segments of the polymer chain are allowed to be randomly oriented in space. Intrinsic disorder is taken into account phenomenologically in the Green's function of the chain. A comparison shows that the contribution of conformational disorder on the line width may be considerable.
ISSN:1058-725X
DOI:10.1080/10587259208047008
出版商:Taylor & Francis Group
年代:1992
数据来源: Taylor
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4. |
Dynamics and Optical Absorption of Electronic Excitations Under the Influence of Coloured Noise |
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Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals,
Volume 218,
Issue 1,
1992,
Page 19-23
P. Reineker,
B. Kaiser,
V. Kraus,
Ch. Warns,
A.M. Jayannavar,
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摘要:
For a model dimer the influence of vibrational degrees of freedom on electronic excitations is described by a dichotomic Markov process with coloured noise. Within this model the energy transport between the two units of the dimer, especially the transition between coherent and incoherent motion is discussed. Furthermore the optical absorption line shape is evaluated for various values of the model parameters.
ISSN:1058-725X
DOI:10.1080/10587259208047009
出版商:Taylor & Francis Group
年代:1992
数据来源: Taylor
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5. |
Picosecond time Resolved Spectra of the Optical Stark Effects on the Stacking Fault Excitons in Bil3Crystals |
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Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals,
Volume 218,
Issue 1,
1992,
Page 25-30
I. Akai,
K. Nakajima,
T. Karasawa,
M. Ichida,
T. Komatsu,
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摘要:
We report the picosecond time resolved spectra of the optical Stark effect on a quasi-two-dimensional exciton localized at a stacking fault plane in Bil3crystals. The ultrafast response of the blue-shift due to the optical Stark effect(OSE) is confirmed in picosecond time domain under negative detuning excitation condition. For positive detuning excitation, an ultrafast switching from the red shift by the OSE to the blue-shift due to the nonlinear interaction with the large amount of incoherent “real” exciton occurs. Under the just resonance excitation, the blue-shift due to the “real” exciton is also observed during several tens of picoseconds after the pumping, and an absorption bleaching occurs at the timing of the pump-pulse peak. The bleaching is discussed in connection with the OSE.
ISSN:1058-725X
DOI:10.1080/10587259208047010
出版商:Taylor & Francis Group
年代:1992
数据来源: Taylor
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6. |
Dephasing and Relaxation Processes on the Stacking Fault Exciton in Bil3Under High Density Excitation |
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Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals,
Volume 218,
Issue 1,
1992,
Page 31-36
M. Ichiad,
T. Kawai,
T. Karasawa,
T. Komatsu,
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摘要:
An exciton confined at a two-dimensional stacking fault in Bi13 crystal reveals large optical nonlinearity and ultra fast response for high density excitation. It shows three resonant luminescences whose decay-time constants are 20ps, 40ps and 900ps from the higher energy states reflecting cascade-type relaxation processes. By the degenerate four-wave mixing (DFWM) measurements, the dephasing times of three exciton states were obtained as 8.6ps, 15ps and 34ps. The dephasing at the lowest state is governed mainly by the LA-phonon intra-band scattering. While, at the higher states, it is governed by the cascade relaxation to the lower states in addition to the phonon scattering. It is found that the dephasing is also influenced by the exciton-exciton scattering under the high density excitation. A nonlinear transition involving a multi-photon process is observed in the excitation response of the DFWM signal. This result suggests the existance of the excitonic molecule.
ISSN:1058-725X
DOI:10.1080/10587259208047011
出版商:Taylor & Francis Group
年代:1992
数据来源: Taylor
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7. |
Excitons Localized in Mesoscopic Domains Produced by Stacking Fault In Bil3 |
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Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals,
Volume 218,
Issue 1,
1992,
Page 37-42
T. Komatsu,
T. Iiad,
K. Murayama,
M. Ichida,
H. Kurisu,
H. Kondo,
I. Akai,
T. Karasawa,
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摘要:
Absorption line series WJ(J=I,II,III,…) appeared below the indirect, edge in BiI3has been studied. The series is assigned to the excitons confined in mesoscopic domains produced by deformation faults characteristic of layered materials. Each line consists of four structures which correspond to x+iy, x-iy, z, and pure triplet states originated from the bulk cationic excitons. The energy separations between these four states are depend on the size of mesoscopic domains in which an exciton is confined. By introducing a disk-like shape model of the mesoscopic domain, the experimental results are analyzed on the basis of anisotropic quantum size effects on the cationic excitons. The relative motion of the exciton is found to be strongly affected by the localization of the translational motion in the direction perpendicular to the confinement axis.
ISSN:1058-725X
DOI:10.1080/10587259208047012
出版商:Taylor & Francis Group
年代:1992
数据来源: Taylor
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8. |
Reversibly Photo-Induced Phase Transition in Single Crystals of Polydiacititlenes |
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Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals,
Volume 218,
Issue 1,
1992,
Page 43-48
Shin-Ya Koshihara,
Yoshinori Tokura,
Takao Koda,
Kenji Takeda,
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摘要:
We have observed novel photo-induced phenomena in conjugated polymers; the reversibly photo-induced phase transitions in single crystals of poly-diacetylene(PDA). Dependence of the phase conversion efficiency on excitation photon energy shows that the photo-generation of charge-carriers (polarons), not excitons, is responsible for the macroscopic phase change.
ISSN:1058-725X
DOI:10.1080/10587259208047013
出版商:Taylor & Francis Group
年代:1992
数据来源: Taylor
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9. |
Quantum Confinement of Translational Motion of Excitons in α-Perylene and Pyrene Microcrystals |
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Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals,
Volume 218,
Issue 1,
1992,
Page 49-54
Ken-Ichi Mizuno,
Atsuo Matsui,
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摘要:
We observed that (1) the luminescence spectra of α-perylene shifted by 440 cm-1as much as the change in the excitation photon energy, from 22100 cm-1(452.5 nm) to 22540 cm-1(443.7 nm), whereas the luminescence spectrum of pyrene shifted by 100 cm-1according as the excitation photon energy in an energy region from 26940 cm (371.2nm) to 26730cm-1(374.1nm), (2) for pyrene microcrystals the luminescence decay under resonant excitation increased as the excitation energy increased, (3) in both materials intense fsee-exciton luminescence was observed but self-trapped exciton luminescence was not.
ISSN:1058-725X
DOI:10.1080/10587259208047014
出版商:Taylor & Francis Group
年代:1992
数据来源: Taylor
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10. |
Optical Absorption Spectra of Sodium Clusters Incorporated into Zeolite Lta |
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Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals,
Volume 218,
Issue 1,
1992,
Page 55-60
Tetsuya Kodaira,
Yasuo Nozue,
Takenari Goto,
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摘要:
Absorption spectra are reported for sodium clusters incorporated into cages of zeolite LTA crystals, where the expected cluster diameter is about 11 Å at maximum. The spectra exhibit the bands originated from the excitation of the quantum-confined electron-hole pair as well as the surface plasmon excitation.
ISSN:1058-725X
DOI:10.1080/10587259208047015
出版商:Taylor & Francis Group
年代:1992
数据来源: Taylor
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