Pii: S0038-1098(99)00576-1
نویسندگان
چکیده
We report a study of single-crystal Raman scattering, powder synchrotron X-ray and neutron diffraction as well as specific heat for the layered compound K2Na[Ag(CN)2]3 in the temperature range 2–300 K. Analysis of the Raman scattering data provides evidence for structural changes at approximately 210 K. Synchrotron X-ray and neutron powder diffraction results indicate essential, gradual changes with temperature in the range from 1.5 to 300 K and in particular small, but significant deviations from trigonal symmetry of the pseudo-hexagonal lattice parameters a aortho= 3 p ; b below approximately 210 K. The c-lattice parameter increases anomalously with decreasing temperature. q 2000 Elsevier Science Ltd. All rights reserved.
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