Approaches for Optimizing the First Electronic Hyperpolarizability of Conjugated Organic Molecules
05 Apr 1991-Science (American Association for the Advancement of Science)-Vol. 252, Iss: 5002, pp 103-106
TL;DR: A two-state, four-orbital, independent electron analysis of the first optical molecular hyperpolarizability, β, leads to the prediction that |β| maximizes at a combination of donor and acceptor strengths for a given conjugated bridge.
Abstract: A two-state, four-orbital, independent electron analysis of the first optical molecular hyperpolarizability, β, leads to the prediction that |β| maximizes at a combination of donor and acceptor strengths for a given conjugated bridge. Molecular design strategies that focus on the energetic manipulations of the bridge states are proposed for the optimization of β. The limitations of molecular classes based on common bridge structures are highlighted and more promising candidates are described. Experimental results supporting the validity of this approach are presented.
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Cites background from "Approaches for Optimizing the First..."
...However, a simple model has been proposed recently in which β is correlated with the degree of ground-state polarizatio...
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01 Jan 1987
3,334 citations
"Approaches for Optimizing the First..." refers background in this paper
...Because the brittle-ductile transition on the fault occurs at a depth of about 20 km (4), the locked segment can extend only about 100 km down dip from the sea-floor trace at the deformation front....
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...properties, which are exploited in telecommunications, data storage, and information processing applications, arise in molecules that lack a center of symmetry (1-4)....
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...Moreover, the shallow extent (maximum depth, 20 km) of the locked segment of the plate interface is consistent with the thermal constraints (4)....
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TL;DR: In this article, a table of donnees (pour de nombreux solvants) des valeurs des parametres M*, α and β donnant respectivement la polarisabilite du solvant, son pouvoir de donneur de proton, and d'accepteur de protons dans les liaisons hydrogene solute-solvant
Abstract: Table de donnees (pour de nombreux solvants) des valeurs des parametres M*, α et β donnant respectivement la polarisabilite du solvant, son pouvoir de donneur de proton, et d'accepteur de protons dans les liaisons hydrogene solute-solvant
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TL;DR: In this paper, the second and third order hyperpolarizabilities of the three nitroaniline isomers and of two related molecules were measured and a theory relating this contribution to the first excited state of energy, oscillator strength, and dipole moment of the molecules was presented.
Abstract: We have measured the second and third order hyperpolarizabilities of the three nitroaniline isomers and of two related molecules. For some isomers the intramolecular charge transfer is found to cause a very large enhancement of the second order polarizabilities. We present a theory relating this contribution to the first excited state of energy, oscillator strength, and dipole moment of the molecules. Experimental results are accounted for with an excellent accuracy.
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TL;DR: In this paper, the non-linear optical polarization of an isolated atom or molecule is treated, giving careful consideration to secular and resonant terms in the perturbation expansion, and the Method of Averages introduced by Bogoliubov and Mitropolsky is used.
Abstract: The non-linear optical polarization of an isolated atom or molecule is treated, giving careful consideration to secular and resonant terms in the perturbation expansion. The Method of Averages introduced by Bogoliubov and Mitropolsky is used. The case where resonance-induced excited state populations are negligible, which is relevant to a wide range of non-linear optical experiments, is examined in detail for polarizations through third order in the perturbing fields. This yields concise expressions which are valid for any combination of applied field frequencies, including static fields.
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TL;DR: In this paper, the electronic origins of nonlinear optical effects in organic π electronic systems are reviewed, with special emphasis being given to second-order nonlinear effects, and the critical relationships of the propagation characteristics of light to observed non-linear optical effect and to solid-state structure are discussed.
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