Lattice dynamics of rare-earth titanates with the structure of pyrochlore R2Ti2O7 (R = Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu): Ab initio calculation

被引:0
作者
V. A. Chernyshev
V. P. Petrov
A. E. Nikiforov
机构
[1] Ural Federal University named after the first President of Russia B. N. Yeltsin,
来源
Physics of the Solid State | 2015年 / 57卷
关键词
Bulk Modulus; Phonon Spectrum; Raman Active Mode; Pyrochlore Structure; Murnaghan Equation;
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摘要
The ab initio calculation has been performed for the crystal structure and the phonon spectrum of titanates with the structure of pyrochlore R2Ti2O7 (R = Gd-Lu). The frequencies and types of fundamental vibrations have been found. For R = Tb, Tm, and Yb, this calculation has been carried out for the first time; furthermore, there is no available information on experimental studies of the phonon spectrum for Tm and Yb. The influence of hydrostatic pressure to 35 GPa on the structure, dynamics, and elastic properties of the Gd2Ti2O7 lattice has been investigated. The dependence of the phonon frequencies on the pressure has been obtained. The calculations have predicted that the relative change in the pyrochlore structure volume during compression at pressures to 35 GPa is well described by the third-order Birch-Murnaghan equation of states. The results of the calculations agree with the available experimental data. It has been shown that the structural, dynamic, and elastic properties of the R2Ti2O7 crystal lattice can be adequately described in the case where the inner shells of the RE ion up to 4f are replaced by the pseudopotential.
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页码:996 / 1002
页数:6
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  • [1] Subramanian M. A.(1983)undefined Prog. Solid State Chem. 15 55-undefined
  • [2] Aravamudan G.(2006)undefined Nanotechnology 17 1745-undefined
  • [3] Subba Rao G. V.(2005)undefined Phys. Solid State 47 1425-undefined
  • [4] Lin K.-M.(1993)undefined J. Chem. Phys. 98 5648-undefined
  • [5] Lin C.-C.(1996)undefined J. Chem. Phys. 105 9982-undefined
  • [6] Li Y.-Y.(2013)undefined J. Cryst. Growth 377 96-undefined
  • [7] Klimin S. A.(2008)undefined Phys. Rev. B: Condens. Matter 77 214310-undefined
  • [8] Popova M. N.(2006)undefined Phys. Rev. B: Condens. Matter 74 064109-undefined
  • [9] Chukalina E. P.(2009)undefined Phys. Rev. B: Condens. Matter 79 214437-undefined
  • [10] Malkin B. Z.(2008)undefined Phys. Rev. B: Condens. Matter 78 214102-undefined