An EPR Investigation of a Nematogen-Like Nitroxide Spin Probe in the Solid Modifications of a Liquid Crystal

  • Arthur E. Stillman
  • Loretta L. Jones
  • Robert N. Schwartz
  • Barney L. Bales


The nematogen-like spin probe N-(p-methoxybenzylidene)-4-amino-2,2,6,6-tetramethylpiperidino-l-oxyl (MBATPO) in the various solid modifications of the liquid crystal MBBA was investigated by EPR spectroscopy. In particular, by cooling the solution in a magnetic field of 6000 G, a nematic glass was prepared and the orientation dependent EPR spectra were studied as a function of the temperature. As the temperature is raised the nematic glass converts irreversibly to the polycrystalline state. The EPR spectra in both solid modifications reveal motional effects which are analyzed utilizing the methods of Freed and co-workers.


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Copyright information

© Springer Science+Business Media New York 1978

Authors and Affiliations

  • Arthur E. Stillman
    • 1
  • Loretta L. Jones
    • 1
  • Robert N. Schwartz
    • 1
  • Barney L. Bales
    • 2
  1. 1.Department of ChemistryUniversity of Illinois at Chicago CircleChicagoUSA
  2. 2.Centro de FisicaI.V.I.C.Venezuela

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