Abstract
PbMo6S8 and SnMo6S8 have low-lying phonon modes involving mainly motion of the Pb or Sn cation. It has long been believed that these cation modes are highly anharmonic. By examining the inelastic neutron scattering, x-ray diffraction, and magnetic susceptibility data in the literature, however, it is shown that these modes are nearly harmonic at room temperature. There is no evidence that they are anharmonic at low temperature. From the observed frequency of the cation modes at room temperature, the delocalization of the cation perpendicular to the trigonal axis is calculated. The calculated delocalization agrees well with that indicated by the x-ray diffraction data.
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References
K. Yvon,Solid State Commun. 25, 327 (1978).
O. Fischer,Appl. Phys. 16, 1 (1978).
H. Nohl, W. Klose, and O. K. Andersen, inCurrent Topics in Materials Science, Vol. 3 (1978), Chapter 6, p. 165.
A. J. Freeman and T. Jarlborg,J. Mag. Mag. Mat. 27, 135 (1982).
K. Yvon, inCurrent Topics in Materials Science, Vol. 3 (1978), Chapter 2, p. 53.
A. W. Webb and R. N. Shelton,J. Phys. F 8, 261 (1978).
J. D. Jorgensen and D. G. Hinks,Solid State Commun. 53, 289 (1985).
S. D. Bader, G. S. Knapp, S. K. Sinha, P. Schweiss, and B. Renker,Phys. Rev. Lett. 37, 344 (1976).
S. D. Bader, S. K. Sinha, and R. N. Shelton, inSuperconductivity in d- and f-Band Metals, D. H. Douglass, ed. (Plenum Press, New York, 1976), p. 209.
B. P. Schweiss, B. Renker, E. Schneider, and W. Reichardt, in Ref. 9, p. 189.
S. D. Bader, S. K. Sinha, B. P. Schweiss, and B. Renker, inCurrent Topics in Materials Science, Vol. 3 (1978), Chapter 7, p. 223.
C. W. Kimball, L. Weber, G. Van Landuy, F. Y. Fradin, B. D. Dunlap, and G. K. Shenoy,Phys. Rev. Lett. 36, 412 (1976).
J. Bolz, J. Hauck, and F. Pobell,Z. Phys. B 25, 351 (1976).
S. D. Bader, G. S. Knapp, and A. T. Aldred,Ferroelectrics 17, 321 (1977).
M. E. Reeves, W. M. Miller, and D. M. Ginsberg,J. Low Temp. Phys. 59, 509 (1985).
W. H. Wright and D. M. Ginsberg,J. Low Temp. Phys. 64, 73 (1986).
E. C. Stoner,Proc. Roy. Soc. A 154, 656 (1936).
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Ginsberg, D.M. An upper limit for the anharmonicity of the cation modes in the superconducting chevrel-phase compounds PbMo6S8 and SnMo6S8 . J Low Temp Phys 68, 399–408 (1987). https://doi.org/10.1007/BF00682304
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DOI: https://doi.org/10.1007/BF00682304