High Pressure Studies of Soft Mode Transitions in Solids

  • G. A. Samara


An overview of the soft mode concept and of high pressure studies of soft; mode transitions in solids is given. Typical results on dis-placive ferroelectric (SbSI) antiferrodistortive [Gd2(MoO4)3 and BaMnF4] transitions as well as on coupled proton-phonon soft mode transitions (KH2PO4) are used to demonstrate that hydrostatic pressure can strongly modify the balance of forces responsible for soft mode behavior. Emphasis is placed on the physical implications of the results and on the general trends of the available data on the different classes of soft mode transitions, for it is such trends that have led to a greater understanding of the nature of the forces involved.


High Temperature Phase Soft Mode Tricritical Point Soft Zone Ferroelectric Transition 
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Copyright information

© Plenum Press, New York 1978

Authors and Affiliations

  • G. A. Samara
    • 1
  1. 1.Sandia LaboratoriesAlbuquerqueUSA

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