London Centre for Nanotechnology and Department of Chemistry, University College London, London WC1E 6BT, UK.
Phys Chem Chem Phys. 2011 Aug 7;13(29):13162-6. doi: 10.1039/c1cp21077g. Epub 2011 Jun 2.
The initial stages of NaCl dissolution in liquid water have been examined with state-of-the-art ab initio molecular dynamics and free energy sampling techniques. Our simulations reveal a complex multi-step process triggered by the departure of Cl ions from the lattice, with a well-defined intermediate state wherein departing ions are partially solvated but remain in contact with the crystal. The polarizability of Cl(-) is identified as the source of the anion's preferential initial dissolution, an effect which leads a forcefield based description of NaCl dissolution to fail to identify a preference for Cl over Na dissolution.
我们采用最先进的从头算分子动力学和自由能采样技术研究了 NaCl 在液态水中的初始溶解阶段。我们的模拟揭示了一个复杂的多步骤过程，该过程由 Cl 离子从晶格中脱离引发，其中存在一个明确的中间状态，即部分被溶剂化的脱离离子仍与晶体接触。Cl(-)的极化率被确定为阴离子优先初始溶解的根源，这一效应导致基于力场的 NaCl 溶解描述未能确定 Cl 相对于 Na 的溶解偏好。
