NEW APPROACH TO DIFFRACTION PATTERN CALCULATION

A new method of calculating diffraction patterns is proposed and teste d on quasicrystals. Using an appropriate defined reference lattice the structure factor can be well approximated by a rapidly convergent ser ies of variable u, which describes the nearest distance between atomic positions and points of the reference lattice. Only the first few ter ms are significant for the diffraction pattern calculation. The possib ility of using the Debye-Waller approximation is also discussed. In th is case an appropriate shift of the reference structure is required. C alculations based on the Debye-Waller formula in real and phason space s give similar results.