Theoretical study of solvent effects of first-order hyperpolarizabilities of nitro-azobenzene dendrimers

Y. Yamaguchi, Y. Yokomichi, Shiyoshi Yokoyama, S. Mashiko

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

The molecular structures of four generations of nitro-azobenzene dendrimers in the nonpolar solvent, carbon tetrachloride (dielectric constant, ε = 2.2) and the polar solvents, chloroform (ε = 4.8) and acetonitrile (ε = 37.5), have been calculated using a molecular dynamics (MD) method. The first-order hyperpolarizabilities (β) were calculated for the MD-calculated structures using the semi-empirical molecular orbital, CNDO/S-CI (complete neglect of differential overlap for spectroscopyconfiguration interaction) level of theory. It was found that the dendrimers show larger β values in the polar solvents with larger dielectric constants, whose characteristics reproduce the experimental results. Although the experimentally observed enhancement of the second harmonic generation (SHG) activity that is greater than the number of chromophores is not sufficiently reproduced, the β values for the second, third, and fourth generations in acetonitrile solution are, respectively, 4.8, 8.0, and 21.7 times that of the first one (98 × 10 -30 esu) of the nitro-azobenzene dendrimers, whose tendency is in good qualitative agreement with the measurements compared to the azobenzene dendrimers without the nitro groups.

Original languageEnglish
Pages (from-to)35-45
Number of pages11
JournalJournal of Molecular Structure: THEOCHEM
Volume578
Issue number1-3
DOIs
Publication statusPublished - Feb 14 2002
Externally publishedYes

Fingerprint

Dendrimers
dendrimers
Theoretical Models
Molecular Dynamics Simulation
acetonitrile
Molecular dynamics
Permittivity
permittivity
molecular dynamics
Carbon Tetrachloride
carbon tetrachloride
Molecular orbitals
Chromophores
Harmonic generation
Chloroform
Molecular Structure
chloroform
Molecular structure
chromophores
harmonic generations

All Science Journal Classification (ASJC) codes

  • Biochemistry
  • Condensed Matter Physics
  • Physical and Theoretical Chemistry

Cite this

Theoretical study of solvent effects of first-order hyperpolarizabilities of nitro-azobenzene dendrimers. / Yamaguchi, Y.; Yokomichi, Y.; Yokoyama, Shiyoshi; Mashiko, S.

In: Journal of Molecular Structure: THEOCHEM, Vol. 578, No. 1-3, 14.02.2002, p. 35-45.

Research output: Contribution to journalArticle

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