Grupo de Pesquisa em Química Inorgânica Teórica (GPQIT), Departamento de Química, ICEx, Universidade Federal de Minas Gerais, 31270-901, Belo Horizonte, MG, Brazil.
J Phys Chem B. 2010 Dec 9;114(48):15941-7. doi: 10.1021/jp110202e. Epub 2010 Nov 15.
A new dynamical discrete/continuum solvation model was tested for NH(4)(+) and OH(-) ions in water solvent. The method is similar to continuum solvation models in a sense that the linear response approximation is used. However, different from pure continuum models, explicit solvent molecules are included in the inner shell, which allows adequate treatment of specific solute-solvent interactions present in the first solvation shell, the main drawback of continuum models. Molecular dynamics calculations coupled with SCC-DFTB method are used to generate the configurations of the solute in a box with 64 water molecules, while the interaction energies are calculated at the DFT level. We have tested the convergence of the method using a variable number of explicit water molecules and it was found that even a small number of waters (as low as 14) are able to produce converged values. Our results also point out that the Born model, often used for long-range correction, is not reliable and our method should be applied for more accurate calculations.
一种新的动力学离散/连续溶剂化模型被用于测试水中 NH(4)(+) 和 OH(-) 离子。该方法类似于连续溶剂化模型，因为它使用了线性响应近似。然而，与纯连续模型不同的是，在内部壳层中包含了显式溶剂分子，这允许对第一溶剂化壳层中存在的特定溶质-溶剂相互作用进行充分处理，这是连续模型的主要缺点。分子动力学计算与 SCC-DFTB 方法相结合，用于在包含 64 个水分子的盒子中生成溶质的构型，而相互作用能则在 DFT 水平上进行计算。我们使用不同数量的显式水分子来测试方法的收敛性，结果发现即使使用少量的水分子（低至 14 个）也能够得到收敛的值。我们的结果还指出，Born 模型（常用于长程校正）是不可靠的，我们的方法应该用于更准确的计算。
