SPECIAL TYPE OF PERIODICITY IN DIFFRACTION PATTERNS OF NON-PERIODIC STRUCTURES

摘要

Periodic series of diffraction peaks, with the periodicity corresponding to the mean distance between the appropriate atomic positions have been found in non-periodic structures (Fibonacci chain). The diffraction intensities have been described by also periodic set of envelope curves. These curves correspond to a set of parallel straight lines in higher-dimensional reciprocal space and they have been obtained by calculations using statistical moments of a specially defined real-space variable describing spatial fluctuation of atomic positions. It has been shown, that such real-space calculations are ftlly equivalent to the higher-dimensional analysis of perfect quasicrystals and can be also used for diffraction analysis of other non periodic structures.