ИСТИНА

Purely resonant reflections of various typescan be observed under resonant diffraction conditionsat incident radiation energies close to the K edge ofyttrium: (4n + 2, 4n', 4n''), (2n + 1, 2n' + 1, 0), (2n, 2n,4n'), which are attributable to the resonant dipole–dipole contribution to the Xray scattering. It follows from these expressions that the (2n + 1,2n'+ 1, 0)type reflections depend only on the tensor component f3(E), while the (4n + 2, 0, 0)type reflections depend on the component difference f2(E) –f1(E). Thus, the tensor of the atomic factor can bereconstructed by studying various types of reflections. Since the resonant absorption near the K absorptionedge of yttrium is proportional to Im[2f2(E) +f1(E)]/3, f1(E) and f2(E) can, in principle, be determined separately from reflection and absorption measurements.