Possible charge inhomogeneities in the CuO2 planes of YBa2Cu3O6¿x „xÄ0.25,0.45,0.65,0.94... from pulsed neutron diffraction
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چکیده
The atomic pair distribution functions ~PDFs! of four powder samples of YBa2Cu3O61x (x 50.25, 0.45, 0.65, 0.94) at 15 K have been measured by means of pulsed neutron diffraction. The PDF is modeled using a full-profile fitting approach to yield structural parameters. In contrast to earlier x-ray absorption fine structure work we find no evidence of a split apical oxygen site. However, a slightly improved fit over the average crystallographic model results when the planar Cu~2! site is split along the c direction. This is interpreted in terms of charge inhomogeneities in the CuO2 planes.
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Possible charge inhomogeneities in the CuO 2 planes of YBa 2 Cu 3 O 6 + x ( x = 0 . 25 , 0 . 45 , 0 . 65 , 0 . 94 ) from pulsed neutron diffraction
The atomic pair distribution functions (PDF) of four powder samples of YBa2Cu3O6+x (x=0.25, 0.45, 0.65, 0.94) at 15 K have been measured by means of pulsed neutron diffraction. The PDF is modelled using a full-profile fitting approach to yield structural parameters. In contrast to earlier XAFS work we find no evidence of a split apical oxygen site. However, a slightly improved fit over the aver...
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