Effect of Hydrostatic Pressure on the Incommensurate Phase of K₂SeO₄

Authors

W. Press, Brookhaven National Laboratory, Upton, New York
C. F. Majkrzak, Brookhaven National Laboratory, Upton, New York
J. D. Axe, Brookhaven National Laboratory, Upton, New York
John R. Hardy, University of Nebraska - LincolnFollow
N. E. Massa, University of Nebraska - Lincoln
F. G. Ullman, University of Nebraska - Lincoln

Date of this Version

7-1-1980

Comments

Published in Physical Review Volume 22, Number 1, 1 July 1980. Copyright 1980. Used by permission.

Abstract

A neutron scattering study of the effect of hydrostatic pressure on the incommensurate phase transformation in K₂SeO₄ was performed in order to obtain information concerning the nature of the competing forces that give rise to a structural instability at a general wave vector. It was found that an increase in pressure lowers the transition temperature (dT_i/dP_i = - 6.5 K/kbar) and results in a smaller value of the initial incommensurate wave vector. The pressure dependence of the incommensurate to ferroelectric phase transition was also investigated (dT_c/dP_c = - 9 K/kbar). The latter transition displays a distinct pressure hysteresis.