Dielectric Dispersion in Hydrated Purple Membrane

  • Imre Kovacs
  • György Varo
Part of the NATO ASI Series book series (NSSA, volume 168)


Dielectric dispersion effects were studied in purple membrane of different hydration levels. The capacitance and conductivity were measured over the frequency range 102Hz to 105Hz. With increase in the hydration level, the conductivity increases sharply at the critical hydration hc=0 .06 gH2O/gbR. This critical hydration is close to the extent of the first continuous strongly bound water layer and is interpreted as the threshold for percolative proton transfer. Above 0.1 gH2O/gbR water content Maxwell-Wagner relaxation also appears, showing the presence of a bulk water phase.


High Water Content Arrhenius Parameter Hydration Level Dielectric Dispersion Purple Membrane 
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Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • Imre Kovacs
    • 1
  • György Varo
    • 2
  1. 1.Central Research Institute for PhysicsBudapest 114Hungary
  2. 2.Institute of BiophysicsBiological Research CenterSzegedHungary

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