Publication
Title
Two variants of the $1/2[110]_{p}(203)_{p}$ crystallographic shear structures: the phasoid $Sr_{0.61}Pb_{0.18}(Fe_{0.75}Mn_{0.25})O_{2.29}$
Author
Abstract
 For the composition (Sr0.61Pb0.18)(Fe0.75Mn0.25)O2.29, a new modulated crystallographic shear structure, related to perovskite, has been synthesized and structurally characterized by transmission electron microscopy. The structure can be described using a monoclinic supercell with cell parameters am = 27.595(2) Å, bm = 3.8786(2) Å, cm = 13.3453(9) Å, and βm = 100.126(5)°, refined from powder X-ray diffraction data. The incommensurate crystallographic shear phases require an alternative approach using the superspace formalism. This allows a unified description of the incommensurate phases from a monoclinically distorted perovskite unit cell and a modulation wave vector. The structure deduced from the high-resolution transmission electron microscopy and high-angle annular dark-field−scanning transmission electron microscopy images is that of a 1/2[110]p(203)p crystallographic shear structure. The structure follows the concept of a phasoid, with two coexisting variants with the same unit cell. The difference is situated at the translational interface, with the local formation of double (phase 2) or single (phase 1) tunnels, where the Pb cations are likely located.
Language
English
Source (journal)
Inorganic chemistry / American Chemical Society. - Easton, Pa
Publication
Easton, Pa : 2009
ISSN
0020-1669
Volume/pages
48:17(2009), p. 8257-8262
ISI
000269313500032
Full text (Publisher's DOI)
UAntwerpen
 Faculty/Department Research group Publication type Subject Affiliation Publications with a UAntwerp address