The structure of monohydrocalcite and the phase composition of the beachrock deposits of Lake Butler and Lake Fellmongery, South Australia

被引：62

作者：

Swainson, Ian P. ^{[1
]}

机构：

[1] Natl Res Council Canada, Canadian Neutron Beam Ctr, Chalk River Labs, Chalk River, ON K0J 1J0, Canada

来源：

AMERICAN MINERALOGIST | 2008年 / 93卷 / 07期

关键词：

monohydrocalcite; carbonate minerals; magnesian-calcite; powder diffraction;

D O I：

10.2138/am.2008.2825

中图分类号：

P3 [地球物理学]; P59 [地球化学];

学科分类号：

0708 ; 070902 ;

摘要：

Samples of beachrock from Lakes Butler and Fellmongery, near Robe, South Australia, were examined by neutron and X-ray powder diffraction. Considerable variation in phase composition was observed, although all samples possessed monohydrocalcite, calcite, aragonite, and magnesian-calcite. The Rietveld refinement of the structure of monohydrocalcite showed significant changes in the orientation of water molecules and a major change in the orientation of a carbonate group with respect to the currently accepted structure. The current refinement shows that the hydrogen-bonding structure consists of three distinct networks, with each of the three carbonate groups being bonded to a single water molecule via one linear and one bifurcated hydrogen bond.

引用

页码：1014 / 1018

页数：5

共 45 条

[1]

BISCHOFF WD, 1983, AM MINERAL, V68, P1183

[2] CALCIUM CARBONATE AND ITS HYDRATES [J].