Epitaxy of Calcite on Mica
Epitaxy of Calcite on Mica
复制标题
方解石在云母上的外延生长
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
H. Christenson
中科院分区：
文献类型：
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作者：
C. J. Stephens;Y. Mouhamad;F. Meldrum;H. Christenson
我们首次报告的条件下，定向生长的方解石发生在白云母云母。在环境湿度（35 - 40%）下风化至少1小时的云母表面上，方解石以平行于基底解理面的（001）取向生长，但在新解理的云母上没有发现外延。纳米薄K2 CO 3微晶是已知的形成在云母表面风化以这种方式，我们的实验表明，这些微晶的存在下，在成核和生长的初始阶段是必要的方解石的外延生长。在这些实验中使用的溶液浓度（≤20 mM）下，钙离子不会吸附到云母表面上，我们认为微晶在表面上提供了补丁，其中碳酸根和钙离子的局部浓度足够高以促进外延生长。
We report for the first time the conditions under which oriented overgrowth of calcite occurs on muscovite mica. Calcite grows in a (001) orientation parallel to the basal cleavage plane on mica surfaces that have been weathered at ambient humidity (35−40%) for periods of at least 1 h, but no epitaxy is found on freshly cleaved mica. Nanometer-thin K2CO3 crystallites are known to form on mica surfaces weathered in this manner, and our experiments show that the presence of these crystallites during the initial stages of nucleation and growth is necessary for the epitaxial growth of calcite. Calcium ions do not adsorb to mica surfaces at the solution concentrations (≤20 mM) used in these experiments, and we suggest that the crystallites provide patches on the surface where the local concentration of both carbonate and calcium ions is high enough to promote epitaxy.