Assisted Desolvation as a Key Kinetic Step for Crystal Growth

详细信息    查看全文

• 作者：Stefano Piana ; Franca Jones ; Julian D Gale
• 刊名：Journal of the American Chemical Society
• 出版年：2006
• 出版时间：October 18, 2006
• 年：2006
• 卷：128
• 期：41
• 页码：13568 - 13574
• 全文大小：565K
• 年卷期：v.128,no.41(October 18, 2006)
• ISSN：1520-5126

文摘

The crystallization of materials from a supersaturated solution is a fundamental chemical process.Although several very successful models that provide a qualitative understanding of the crystal growthprocess exist, in most cases the atomistic detail of crystal growth is not fully understood. In this work,molecular dynamics simulations of the morphologically most important surfaces of barite in contact with asupersaturated solution have been performed. The simulations show that an ordered and tightly boundlayer of water molecules is present on the crystal surface. The approach of an ion to the surface requiresdesolvation of both the surface and the ion itself leading to an activated process that is rate limiting fortwo-dimensional nucleation to occur. However, desolvation on specific surfaces can be assisted by anionsadsorbed on the crystal surface. This hypothesis, corroborated by crystallization and scanning electronmicroscopy studies, allows the rationalization of the morphology of barite crystals grown at differentsupersaturations.