A shift-lattice description of some face centred cubic alloy superstructures

Abstract

Both metal atom components of a number of binary alloy structures, mainly occurring in the Au-rich region of the Au–Mn system, have been analysed as shift-lattices. It is shown that both atom types lie upon separate complementary shift-lattices. All the structures can be reproduced by a smooth variation of the shift-lattice parameters. Those found experimentally form only a small set of the infinite family of commensurate and incommensurate structures which can be constructedvia the shift-lattice method. The diffraction patterns of these phases can readily be derived and the relationship of the diffraction patterns observed to the separate components from each of the contributing shift-lattices is described.

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