Structure of incommensurately modulated chromium pyrophosphate studied by Maximum Entropy Method (MEM)
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چکیده
منابع مشابه
Structure of incommensurate ammonium tetrafluoroberyllate studied by structure refinements and the maximum entropy method.
Incommensurately modulated ammonium tetrafluoroberyllate (AFB) occurs in a narrow temperature interval between the paraelectric room-temperature phase with space group Pnma (Ti = 178 K) and the ferroelectric low-temperature phase with space group Pna2(1) (Tc = 173 K). The structure is determined from accurate single-crystal X-ray diffraction data collected with synchrotron radiation at 175 K. T...
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High-resolution x-ray powder-diffraction experiments were performed on europium metal at high pressure up to 50 GPa. At variance with previous reports, the hcp phase of Eu was observed to be stable not only to 18 GPa, but to 31.5 GPa. At 31.5(5) GPa, europium transforms to a phase (Eu-IV) with an incommensurately modulated monoclinic crystal structure with superspace group C2/c(q(1)0q(3))00. Th...
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ژورنال
عنوان ژورنال: Journal of Physics: Conference Series
سال: 2010
ISSN: 1742-6596
DOI: 10.1088/1742-6596/226/1/012012