Application of Generalized Van Der Waals Theory of Homologous Nematogens — Part 1: Trans-4-Ethoxy-4’-N-Alkanoyloxyazobenzenes

  • Andrew C. Pineda
  • Todd J. Jones
  • Gerald R. Van Hecke

Abstract

In the generalized van der Waals theory (GVDW) of Cotter, nematogens are viewed as rigid spherocylinders moving in a mean field potential given by V(θ) = -λovo0ρ-λ2vo ρ ηP2(cos θ) where λo and λ2 are potential parameters independent of temperature. Employing the equation of state developed by Cotter, values of λo, λ2, and the order parameter are calculated for a homologous series of trans-4-ethoxy-4’-alkanoyloxyazobenezenes from observed volume and temperature data. Calculated λo values were found to be 3 to 5 times those calculated from heat of vaporization estimates. In calculating the temperature dependence of the order parameter, the λ2 values were found to vary markedly with temperature. In addition, calculated values of the order parameter were generally about one-half to one-third of the experimentally measured values.

Keywords

Enthalpy Benzene Alkane Alben Aniso 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    See for example:Google Scholar
  2. A. Wulf, A. G. DeRocco, J. Chem. Phys., 55, 12 (1971).CrossRefGoogle Scholar
  3. S. Marcelja, J. Chem. Phys., 60, 3599 (1974).CrossRefGoogle Scholar
  4. R. Alben, Mol. Cryst. Liq. Cryst., 13, 193 (1971).CrossRefGoogle Scholar
  5. W. Maier, A. Saupe, Z. Naturforsch, A14 882 (1959).Google Scholar
  6. 2.
    M. A. Cotter, J. Chem. Phys., 66, 1098 (1977).CrossRefGoogle Scholar
  7. 3.
    W. A. Gelbart, B. A. Baron, J. Chem. Phys., 66, 207 (1977).CrossRefGoogle Scholar
  8. 4.
    W. A. Gelbart, Barboy, Acc. Chem. Res., 13, 290 (1980).CrossRefGoogle Scholar
  9. 5.
    B. A. Baron, W. A. Gelbart, J. Chem. Phys., 67 (12), 5796 (1977).CrossRefGoogle Scholar
  10. 6.
    D. A. Dunmur, W. H. Miller, J. de Physique, C3, 40, C3 - 141 (1979).Google Scholar
  11. 7.
    G. R. Van Hecke, J. Stecki, Phys. Rev. A., 25, 1123 (1982).CrossRefGoogle Scholar
  12. 8.
    C. L. Hillemann, G. R. Van Hecke, S. R. Peak, J. B. Winther, M. A. Rudat, D. A. Kalman, M. L. White, J. Phys. Chem., 79, 1566 (1975).CrossRefGoogle Scholar
  13. 9.
    B. D. Santarsiero, L. J. Theodore, unpublished results.Google Scholar
  14. 10.
    G. R. Van Hecke, B. D. Santarsiero, L. J. Theodore, Mol. Cryst. Liq. Cryst., 45, 1 (1978).Google Scholar

Copyright information

© Plenum Press, New York 1984

Authors and Affiliations

  • Andrew C. Pineda
    • 1
  • Todd J. Jones
    • 1
  • Gerald R. Van Hecke
    • 1
  1. 1.Department of ChemistryHarvey Mudd CollegeClaremontUSA

Personalised recommendations