Light Scattering Studies of the Two-Dimensional Phase Transition in Squaric Acid

  • Erling Fjær
  • Jorunn Grip
  • Emil J. Samuelsen
Part of the NATO Advanced Study Institutes Series book series (NSSB, volume 50)


Crystalline squaric acid, H2C4O4, has attracted considerable interest among physicists due to its simple planar geometry [1] and the existence of a structural phase transition at about 100 C [2]. Since proton ordering in hydrogen “bonds seems to play a key role in the phase change, it was soon realized that one had at hand a material which might show interesting two-dimensional Ising-type behaviour [3]. Information gained from birefringence studies [2] and neutron scattering [3] did in fact support such a view.


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Copyright information

© Plenum Press, New York 1980

Authors and Affiliations

  • Erling Fjær
    • 1
  • Jorunn Grip
    • 1
  • Emil J. Samuelsen
    • 1
  1. 1.Institutt for Almen Fysikk, Norwegian Institute of TechnologyUniversity of TrondheimTrondheim-NTHNorway

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