Enhanced (001) anomalous scattering by YBa2Cu3O7-d 50 nm films on SrTiO3
substrates with and without a grain boundary versus temperature is interpreted
using crystallographic weights to distinguish it from total electron yield and
fluorescence spectra. The power of diffraction enhancement is to ascertain the
film oxygen composition from the changes in the c-axis, c0 as the film surface
is scanned across the grain boundary, and to determine that c0 is constant
versus temperature across the superconducting phase transition.Comment: 4 pages, 6 figure