A Molecular Dynamics Study of the Early Stages of Calcium Carbonate Growth

作者:Tribello Gareth A*; Bruneval Fabien; Liew CheeChin; Parrinello Michele
来源:Journal of Physical Chemistry B, 2009, 113(34): 11680-11687.
DOI:10.1021/jp902606x

摘要

The precipitation of calcium carbonate in water has been examined using a combination of molecular dynamics and umbrella sampling. During 20 ns molecular dynamics trajectories at elevated calcium carbonate concentrations, amorphous particles are observed to form and appear to be composed of misaligned domains of vaterite and aragonite. The addition of further calcium ions to these clusters is found to be energetically favorable and virtually barrierless. By contrast, there is a large barrier to the addition of calcium to small calcite crystals. Thus, even though calcite nanocrystals are stable in solution, at high supersaturations, particles of amorphous material form because this material grows much faster than ordered calcite nanocrystals.

  • 出版日期2009-8-27
  • 单位中国地震局