Growth of Calcite in Confinement

Crystals

Lei Li¹  Anja Røyne¹  Dag Kristian Dysthe¹  Felix Kohler¹ 

[1] Condensed Matter Section and Physics of Geological Processes, Department of Physics, University of Oslo, P. O. Box 1048 Blindern, 0316 Oslo, Norway;

关键词: crystal growth;    calcite;    microfluidic;    nanoconfinement;    reflection interference contrast microscopy;   

DOI  :  10.3390/cryst7120361

来源: DOAJ

【 摘 要 】

Slow growth of calcite in confinement is abundant in Nature and man-made materials. There is ample evidence that such confined growth may create forces that fracture solids. The thermodynamic limits are well known, but since confined crystal growth is transport limited and difficult to control in experiments, we have almost no information on the mechanisms or limits of these processes. We present a novel approach to the in situ study of confined crystal growth using microfluidics for accurate control of the saturation state of the fluid and interferometric measurement of the topography of the growing confined crystal surface. We observe and quantify diffusion-limited confined growth rims and explain them with a mass balance model. We have quantified and modeled crystals “floating” on a fluid film of 25–50 nm in thickness due to the disjoining pressure. We find that there are two end-member nanoconfined growth behaviors: (1) smooth and (2) rough intermittent growth, the latter being faster than the former. The intermittent growth rims have regions of load- bearing contacts that move around the rim causing the crystal to “wobble” its way upwards. We present strong evidence that the transition from smooth to rough is a generic confinement-induced instability not limited to calcite.

【 授权许可】

Unknown