On the crystal structure of Fe6Ce5 and its relationship to B8-type structures

Epitaxial intergrowths of Fe6Ge5 and B8-type Fe1+xGe was investigated by me ans of electron diffraction, A crystal structure description of Fe6Ge5 in t erms of B8- and B1-type structures was established; 4/5 of the Ce atoms in Fe6Ge5 can be described with one-octahedron wide slabs of hexagonal close-p acked Ce atoms with all octahedral sites and 1/2 of the trigonal bipyramida l sites therein filled with Fe atoms (B8), Additionally, all Ge atoms can b e described by a two-octahedra wide slab of cubic close-packed Ge atoms wit h 4/6 of the octahedral sites filled with Fe atoms and 1/6 of the octahedra l sites filled with two Fe atoms, one in each square pyramid (B1), At the s urface interconnecting these slabs, octahedra from the B8 and B1 slabs shar e faces and the trigonal bipyramid from the hcp array and two edge-sharing tetrahedra from the ccp array are merged to form a pentagonal bipyramid, (C ) 1998 Academic Press.