Department of Physical Chemistry, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Geneva, Switzerland.
J Phys Chem B. 2010 Dec 2;114(47):15590-7. doi: 10.1021/jp105590h. Epub 2010 Nov 5.
We present the results of a quantum chemical and classical molecular dynamics simulation study of some solutions containing chloride salts of La(3+), Gd(3+), and Er(3+) at various concentrations (from 0.05 to 5 M), with the purpose of understanding their structure and dynamics and analyzing how the coordination varies along the lanthanide series. In the La-Cl case, nine water molecules surround the central La(3+) cation in the first solvation shell, and chloride is present only in the second shell for all solutions but the most concentrated one (5 M). In the Gd(3+) case, the coordination number is ∼8.6 for the two lowest concentrations (0.05 and 0.1 M), and then it decreases rapidly. In the Er(3+) case, the coordination number is 7.4 for the two lowest concentrations (0.05 and 0.1 M), and then it decreases. The counterion Cl(-) is not present in the first solvation shell in the La(3+) case for most of the solutions, but it becomes progressively closer to the central cation in the Gd(3+) and Er(3+) cases, even at low concentrations.
我们呈现了一项量子化学和经典分子动力学模拟研究的结果，该研究涉及含有 La(3+)、Gd(3+) 和 Er(3+) 氯化盐的一些溶液，浓度范围从 0.05 到 5 M，旨在了解它们的结构和动力学，并分析配位如何沿镧系元素系列变化。在 La-Cl 情况下，在第一个溶剂化壳中，有九个水分子围绕着中心 La(3+)阳离子，而在所有溶液中（除了最浓的一种（5 M）之外），只有氯离子存在于第二个壳层中。在 Gd(3+)情况下，对于两个最低浓度（0.05 和 0.1 M），配位数约为 8.6，然后迅速下降。在 Er(3+)情况下，对于两个最低浓度（0.05 和 0.1 M），配位数为 7.4，然后下降。在大多数溶液中，La(3+)情况下的反离子 Cl(-)不存在于第一个溶剂化壳层中，但在 Gd(3+)和 Er(3+)情况下，它逐渐靠近中心阳离子，即使在低浓度下也是如此。
