Resonant x-ray scattering from chiral materials: α-quartz, α-berlinite, and tellurium

Abstract

We study the resonant x-ray scattering (RXS) at Si K, Al K and Te Ll-edges from chiral materials, α-quartz, α-berlinite, and tellurium. For the forbidden reflections (001) and (001̄), we deduce the scattering matrix for the El El event by summing up the local scattering matrices. The oscillation terms proportional to cos (3Ψ δ) and sin (3Ψ δ) are obtained in the spectral intensity as a function of azimuthal angle Ψ with an expression of possible phase shift δ. We evaluate the parameters which cannot be determined in the symmetry argument on the basis of underlying electronic structures given by the bond-orbital model calculation for α-quartz and α-berlinite, and by using the FLAPW band structure calculation based on the local density approximation for tellurium. The calculated spectra reproduce well the experimental results which depend on photon polarization and crystal chirality. We point out that the finite core-hole life-time and the band effect in the intermediate states may cause together the phase shift δ.