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Title: Second-harmonic generation in a polymer Langmuir - Blodgett film

Abstract

Second-harmonic generation was used to investigate nonlinear optical properties and the structure of multilayer Langmuir - Blodgett films of a copolymer of fluoroalkylmethacrylate with methacrylates containing an azo dye and a cinnamoyl group inside a chain. Quantum-chemical calculations were made of the components of the molecular hyperpolarisability tensor in which the intermolecular interactions were taken into account. The orientation of nonlinear optical fragments of a polymer chain relative to the substrate and components of the quadratic optical susceptibility tensor of the film were determined. (nonlinear optical phenomena)

Authors:
; ;  [1]; ;  [2];  [3]
  1. Institute of Macromolecular Compounds, Russian Academy of Sciences, St. Petersburg (Russian Federation)
  2. A.M. Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)
  3. Institute of Physical Chemistry, Russian Academy of Sciences, Moscow (Russian Federation)
Publication Date:
OSTI Identifier:
21439447
Resource Type:
Journal Article
Resource Relation:
Journal Name: Quantum Electronics (Woodbury, N.Y.); Journal Volume: 28; Journal Issue: 9; Other Information: DOI: 10.1070/QE1998v028n09ABEH001328
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AZO DYES; COPOLYMERS; FILMS; HARMONIC GENERATION; INTERMOLECULAR FORCES; LAYERS; METHACRYLATES; NONLINEAR OPTICS; OPTICAL PROPERTIES; SUBSTRATES; TENSORS; AZO COMPOUNDS; CARBOXYLIC ACID SALTS; DYES; FREQUENCY MIXING; OPTICS; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; ORGANIC POLYMERS; PHYSICAL PROPERTIES; POLYMERS

Citation Formats

Ivanova, V N, Kudryavtsev, V V, Lebedeva, G K, Maslyanitsyn, I A, Shigorin, V D, and Chudinova, G K. Second-harmonic generation in a polymer Langmuir - Blodgett film. United States: N. p., 1998. Web. doi:10.1070/QE1998V028N09ABEH001328.
Ivanova, V N, Kudryavtsev, V V, Lebedeva, G K, Maslyanitsyn, I A, Shigorin, V D, & Chudinova, G K. Second-harmonic generation in a polymer Langmuir - Blodgett film. United States. doi:10.1070/QE1998V028N09ABEH001328.
Ivanova, V N, Kudryavtsev, V V, Lebedeva, G K, Maslyanitsyn, I A, Shigorin, V D, and Chudinova, G K. Wed . "Second-harmonic generation in a polymer Langmuir - Blodgett film". United States. doi:10.1070/QE1998V028N09ABEH001328.
@article{osti_21439447,
title = {Second-harmonic generation in a polymer Langmuir - Blodgett film},
author = {Ivanova, V N and Kudryavtsev, V V and Lebedeva, G K and Maslyanitsyn, I A and Shigorin, V D and Chudinova, G K},
abstractNote = {Second-harmonic generation was used to investigate nonlinear optical properties and the structure of multilayer Langmuir - Blodgett films of a copolymer of fluoroalkylmethacrylate with methacrylates containing an azo dye and a cinnamoyl group inside a chain. Quantum-chemical calculations were made of the components of the molecular hyperpolarisability tensor in which the intermolecular interactions were taken into account. The orientation of nonlinear optical fragments of a polymer chain relative to the substrate and components of the quadratic optical susceptibility tensor of the film were determined. (nonlinear optical phenomena)},
doi = {10.1070/QE1998V028N09ABEH001328},
journal = {Quantum Electronics (Woodbury, N.Y.)},
number = 9,
volume = 28,
place = {United States},
year = {Wed Sep 30 00:00:00 EDT 1998},
month = {Wed Sep 30 00:00:00 EDT 1998}
}
  • Nonlinear second harmonic generation (SHG), second harmonic microscopy (SHM), and infrared spectroscopy are used to determine the structural and optical properties of the Langmuir-Blodgett (LB) monolayer assemblies of NLO-active, 4-eicosyloxo-(E)-stilbazolium iodide (4-EOSI) on a glass substrate. The packing characteristics of the pretransferred interfacial films are determined using {pi}-A isotherm measurements. The molecular coverage of the transferred films is determined by ellipsometry. The films formed on both sides of the glass substrate show substantial second harmonic (SH) conversion from p-polarized 1064 nm fundamental excitation. The SHG and FTIR measurements imply that the single LB layer on glass is composed of orientedmore » clusters of 4-EOSI molecules that are laterally discontinuous. Ordered clusters up to 40 {micro}m in diameter are directly observed using SHM. Subsequent LB transfers using the same 4-EOSI molecule or an amphiphile of comparable chain-length (eicosanoic acid) fill in the unoccupied vacancies in the first layer. The magnitude of the dominant element of the nonlinear susceptibility and the average molecular orientation angle of the chromophore are determined by modeling the characteristic SHG Maker fringes.« less
  • Both the Langmuir and Langmuir-Blodgett films of a C[sub 60] derivative C[sub 60](C[sub 4]H[sub 8]N[sub 2]) at the air-water interface have been prepared. The second-order molecular hyperpolarizability is determined to be (3.6 [+-] 1.2) x 10[sup 29] esu. 29 refs., 3 figs., 1 tab.
  • The rare-earth coordination compound (E)-N-hexadecyl-4-(2-(4-(dimethylamino)phenyl)-ethenyl)pyridinium tetrakis(1-phenyl-3-methyl-4-benzoyl-5-pyrazolonato)dysprosium(III) was synthesized. The LB films were prepared and characterized by UV-vis, IR, X-ray photoelectron spectroscopy, and low-angle X-ray diffraction. High-quality LB films up to 50 layers on the hydrophilic substrates of quartz, calcium fluoride, and glass were obtained. From the second-harmonic generation measurement, second-order molecular hyperpolarizability {beta} of the dysprosium complex was estimated to be about (6.6-9.3) x 10{sup {minus}28} esu. 14 refs., 6 figs., 1 tab.
  • The second harmonic signal from monolayers of retinal and retinal Schiff bases is reported. The results have yielded information on the monolayer structure and demonstrate that retinal and retinal Schiff bases have large second-order molecular hyperpolarizabilities with values of 1.4 x 10/sup -28/, 1.2 x 10/sup -28/, and 2.3 x 10/sup -28/ esu for retinal, the unprotonated Schiff base, and the protonated Schiff base, respectively. These values compare well with the known variation in the alteration in the dipole moment of such chromophores upon excitation.
  • A series of amphiphilic lanthanide complexes were designed and synthesized, in which the lanthanide complex anions act both as the counterions of hemicyanine and as the spacer within a Langmuir-Blodgett (LB) film. Studies on the surface pressure-area ({pi}-A) isotherms of these complexes show that the film-forming properties can be clearly improved if appropriate {Beta}-diketone ligands were chosen. The effects of molecular structures of the complexes, including the variation of lanthanide central ions, the structures of {Beta}-diketone ligands, and the length of alkyl chains in hemicyanines, on the film-forming properties of the materials are discussed. From second-harmonic generation experiments, the largelymore » enhanced second-order molecular hyperpolarizability of lanthanide complexes with good film-forming properties were obtained compared with the hemicyanine iodide. This effect may be due in part to the local field effect but primarily molecular ordering and ordered segregation of hemicyanine chromophores by the bulky lanthanide complex anions. The charge separation of the hemicyanine chromophores was supported by the crystal structure of a model complex. The homogeneity of the film was verified by low angle X-ray diffraction and also by the linear relationship of the absorbance vs the number of layers of the LB films of a selected complex. 37 refs., 7 figs., 3 tabs.« less