The crystal structure of CaSiO3-walstromite, a special isomorph of wollastonite-II

The crystal structure of CaSiO -walstromite has been solved and refined by a data set collected from an inclusion in a diamond single crystal (1135 observed reflections, Mo , Nonius CAD4, = 3.46). The crystal structure is almost identical to that of walstromite (Ca BaSi ). The replacement of Ba by C...

Full description

Saved in:
Bibliographic Details
Published inZeitschrift für Kristallographie. Crystalline materials Vol. 218; no. 12; pp. 811 - 818
Main Authors Joswig, Werner, Paulus, Erich F., Winkler, Björn, Milman, Victor
Format Journal Article
LanguageEnglish
Published De Gruyter Oldenbourg 01.12.2003
Online AccessGet full text

Cover

More Information
Summary:The crystal structure of CaSiO -walstromite has been solved and refined by a data set collected from an inclusion in a diamond single crystal (1135 observed reflections, Mo , Nonius CAD4, = 3.46). The crystal structure is almost identical to that of walstromite (Ca BaSi ). The replacement of Ba by Ca causes no significant structural changes (ring silicate; according to F. Liebau: single rings). The structural differences to wollastonite-II (Ca Si ) are also relatively small: The Ca positions are almost the same, but the axial Si -ring is isomorphously replaced by the same ring with the inverse axiality. This constitutes a new principle of isomorphous replacement. Based on density functional theory the equation of state has been predicted. This allows us to estimate the remaining pressure of the investigated CaSiO inclusion in the diamond to be ≈3 GPa.
ISSN:2194-4946
2196-7105
DOI:10.1524/zkri.218.12.811.20547