Domain size modelling in yba₂cu₃0_7−δ powders and powdered single crystals by means of X-ray diffraction

Abstract

To cite this article: M. Rand , J. I. Langford & J. S. Abell (1993) Domain size modelling in yba 2 cu 3 0 7−δ powders and powdered single crystals by means of X-ray diffraction, Philosophical Magazine Part B, 68:1, 17-28,

Observations of twinning in YBa2Cu3O6 x, 0 <x< 1, at high temperatures

“…These authors demonstrated that the orthorhombicity disappeared in a continuous fashion as the system approached the phase boundary, implying a second-order transition. On the other hand, Rand et al [18] observed a region of co-existence of the T and the split OI reflections, which would normally be taken to imply a first-order transition. The objective of the present paper is to investigate whether twinning occurs at high temperatures and how its existence can be related to a second-order phase transition.…”

Crystallite size distribution and dislocation structure determined by diffraction profile analysis: principles and practical application to cubic and hexagonal crystals

“…It can be shown that, once the strain contribution has been separated, diffraction peak pro®les depend on the shape, the mean size and the size distribution of crystallites or coherently diffracting domains (Bertaut, 1950;Rao & Houska, 1986;Langford et al, 2000). If the shape of the crystallites can be assumed to be uniform, the area-and volume-weighted mean crystallite sizes can be determined from the Fourier coef®cients and the integral breadths of the X-ray diffraction pro®les (Krill & Birringer, 1998;Rand et al, 1993;Wilson, 1962;Gubicza et al, 2000). These two mean sizes of crystallites can be used for the determination of a crystallite size distribution function.…”

The microstructure of mechanically alloyed Al–Mg determined by X-ray diffraction peak profile analysis

“…The standard methods of X-ray diffraction profile analysis based on the full width at half-maximum (FWHM), the integral breadths and on the Fourier coefficients of the profiles provide the apparent crystallite size and the mean-square strain [3][4][5][6]. If the crystallites in a material can be assumed to have the same shape, a crystallite size distribution function having two free parameters can be also determined [7][8][9][10][11][12]. The evaluation of the X-ray profiles is complicated by the anisotropic strain broadening of the diffraction peaks [13][14][15].…”