Layer-by-Layer Growth of Acentric Multilayers of Zr and Azobenzene Bis(phosphonate): Structure, Composition, and Second-Order Nonlinear Optical Properties

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• 作者：Grace A. Neff ; Marcus R. Helfrich ; Matthew C. Clifton ; and Catherine J. Page
• 刊名：Chemistry of Materials
• 出版年：2000
• 出版时间：August 2000
• 年：2000
• 卷：12
• 期：8
• 页码：2363 - 2371
• 全文大小：115K
• 年卷期：v.12,no.8(August 2000)
• ISSN：1520-5002

文摘

This paper describes the use of layer-by-layer growth of metal-bis(phosphonate) multilayers to produce acentric thin films with second-order nonlinear optical properties. Toincorporate such properties, organic "chromophore" molecules containing conjugated systems situated between electron donor and electron acceptor groups are oriented uniformlywithin the film such that the bulk structure is noncentrosymmetric. This is accomplishedusing chromophoric ,-bis(phosphonate) molecules that have one terminal phosphonategroup "protected" in ester form, whereas the other is a free phosphonic acid that will bindto a metal-primed silicon or glass surface. After deposition of the acid moiety onto metal-primed silicon, the ester groups are hydrolyzed to enable deposition of additional metal andchromophore layers. We report here the results of this approach using the chromophorebis(1-ethyl)3-{N-methyl[(4-[(4-phenylphosphonic acid)azo]phenyl)amino]decyl}phosphonate,or azobenzene molecule I. Results from multilayer studies and monolayer and solution studiesare discussed, with emphasis on results from UV-vis spectroscopy, grazing angle X-raydiffraction, and second harmonic generation.