Showing papers on "Pentacene published in 1984"
TL;DR: By means of Penningionization electron spectroscopy, the outermost surface layer of a pentacene film on a graphite substrate (cleavage plane) was selectively observed.
Abstract: By means of Penning-ionization electron spectroscopy the outermost surface layer of a pentacene film on a graphite substrate (cleavage plane) was selectively observed. Ultraviolet photoelectron spectroscopy was also applied to observe several layers from the surface. From the analyses of the two types of spectra the subtle changes in the electronic state and the molecular orientation of the outermost layer and also those of inner layers were probed separately during the layer-by-layer epitaxial growth of the film.
80 citations
TL;DR: In this article, calculations for evidently non-rigid molecules of aromatic hydrocarbons have been carried out on tetracene and pentacene and significant differences can be noted between results from a "rigid-body" and a "nonrigid" treatment.
31 citations
TL;DR: The triplet kinetics of pentacene imbedded in p‐terphenyl and benzoic acid crystals have been studied by electron spin echo spectroscopy in the temperature range of 77-300 K as mentioned in this paper.
Abstract: The triplet kinetics of pentacene imbedded in p‐terphenyl and benzoic acid crystals have been studied by electron spin echo spectroscopy in the temperature range of 77–300 K. Population inversions have been observed for both H0‖‖x and H0‖‖z in the benzoic acid crystal but only for H0‖‖z in the p‐terphenyl crystal at room temperature. Detailed analyses showed that the triplet population and decay of the pentacene are very much host and temperature dependent. Dimer formation and tautomerization (proton transfer of the benzoic acid dimer) may be responsible for the peculiar triplet kinetics of the pentacene in the benzoic acid crystal.
30 citations
TL;DR: In this paper, a theory of dispersive transport with bulk generation is formulated in order to explain the experimental results, based on the concept of transport controlled by carrier trapping on localised levels distributed over a wide energy region.
Abstract: This paper presents an experimental study of carrier drift in polycrystalline pentacene layers under small-signal conditions. The shape of the transient current, caused by pulsed bulk carried generation, and the transit time field-dependence are analysed in detail for various temperatures. The data obtained indicate a dispersive transport regime. A theory of dispersive transport with bulk generation is formulated in order to explain the experimental results. The theory is based on the concept of transport controlled by carrier trapping on localised levels distributed over a wide energy region. Particular attention is given to the exponential and Gaussian models of trap energy distribution. The Gaussian model seems more realistic for interpretation of experimental data on polycrystalline pentacene layers.
29 citations
TL;DR: In this paper, a comparison of experiments on tetracene and pentacene dimers was performed to determine the mechanism responsible for temperature-dependent optical dephasing, which was shown that excitation of librations rather than scattering between delocalized dimer states is the principal mechanism.
25 citations
TL;DR: The triplet kinetics of pentacene imbedded in p‐terphenyl and benzoic acid crystals have been studied by electron spin echo spectroscopy in the temperature range of 77-300 K.
Abstract: The triplet kinetics of pentacene imbedded in p‐terphenyl and benzoic acid crystals have been studied by electron spin echo spectroscopy in the temperature range of 77–300 K. Population inversions have been observed for both H0‖‖x and H0‖‖z in the benzoic acid crystal but only for H0‖‖z in the p‐terphenyl crystal at room temperature. Detailed analyses showed that the triplet population and decay of the pentacene are very much host and temperature dependent. Dimer formation and tautomerization (proton transfer of the benzoic acid dimer) may be responsible for the peculiar triplet kinetics of the pentacene in the benzoic acid crystal.
3 citations
TL;DR: In this article, the electric and magnetic properties of the charge transfer complexes of tetrabenzo[de,hi,op,st]pentacene (TBPA) with various Cs compositions have been investigated.
Abstract: The electric and magnetic properties of the charge transfer complexes of tetrabenzo[de,hi,op,st]pentacene (TBPA) with various Cs compositions have been investigated. The nonplanarity of a TBPA nanocyclic aromatic molecule causes the restriction against complex formation in contrast with other nanocyclic ones, TBPA-Cs complexes were good conductors, which was consistent with their characteristics of a partial charge transfer.