In:
Zeitschrift für Kristallographie - Crystalline Materials, Walter de Gruyter GmbH, Vol. 229, No. 5 ( 2014-5-1), p. 353-367
Abstract:
The atomic structure of the incommensurate Pd 5 B 1-z phase has been analysed in detail by selected area electron diffraction and neutron-powder diffraction. That structure is based on a close-packed cubic arrangement of Pd atoms with the B atoms occupying the octahedral sites in a long-range ordered fashion. The ordering pattern of B is an incommensurately modulated one with a modulation vector of a length which changes with the B content ( ~ PdB 0.18-0.19 ) to adapt the ordering pattern continuously to the actual composition. The structure can be conceived to be constituted from “isolated” BPd 6 units (also occurring in the previously reported Pd 6 B phase) and edge-sharing B 2 Pd 10 octahedra units, which occur in a ratio reflecting the actual B content. As predicted on the basis of elastic interactions between B atoms, nearest neighbour B-B pairs occur (the B 2 Pd 10 double octahedra units) in the structure of the Pd 5 B 1-z phase, whereas occurrence of second-nearest neighbour B-B pairs is avoided. For the ideal composition Pd 5 B the crystal structure of the Pd 5 B 1-z phase corresponds to that of monoclinic UCl 5 with U playing the role of B and Cl that of Pd.
Type of Medium:
Online Resource
ISSN:
2196-7105
,
2194-4946
DOI:
10.1515/zkri-2013-1710
Language:
English
Publisher:
Walter de Gruyter GmbH
Publication Date:
2014
SSG:
13
