The commensurately modulated structure of the lock-in phase of synthetic Co-akermanite, Ca2CoSi2O7

被引：0

作者：

Riester, M

Böhm, H ^{[1
]}

Petricek, V

机构：

[1] Univ Mainz, Inst Geowissensch, D-55099 Mainz, Germany

[2] Acad Sci Czech Republ, Inst Phys, Prague 18221 8, Czech Republic

来源：

ZEITSCHRIFT FUR KRISTALLOGRAPHIE | 2000年 / 215卷 / 02期

关键词：

D O I：

暂无

中图分类号：

O7 [晶体学];

学科分类号：

0702 ; 070205 ; 0703 ; 080501 ;

摘要：

This paper deals with the structure determination of the lock-in phase of synthetic modulated Co-akermanite, Ca2CoSi2O7 The structure determination of the (3 x 3 x 1) superstructure is based on X-ray data of a twinned single crystal taken at 130 K. The deformation modes in the commensurate lock-in phase are derived and compared with the deformations found by other authors in the incommensurate phase. A model for the driving force of the modulation in melilites in general is proposed: In order to release internal stress domains with clusters of 6-and 7-fold coordinated calcium are formed which are arranged in octagons.

引用

页码：102 / 109

页数：8

共 9 条

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