论文信息 - Anharmonic Thermal Atomic Vibrations in the Cubic Phase of Cs2NaNdCl6 Single Crystals

Anharmonic Thermal Atomic Vibrations in the Cubic Phase of Cs2NaNdCl6 Single Crystals

Thermal atomic vibrations in the cubic phase of Cs2NaNdCl6 single crystal undergoing the structural phase transition (PT) at 138 K are investigated from the data of X-ray diffraction obtained at 278, 218, and 148 K. A significant anisotropy of thermal vibrations and their deviations from harmonic behaviour are found for the Cl-atoms of the structure. These atoms displace from their equilibrium positions below PT due to the tilts of the octahedral groups. [Russian Text Ignored].

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