A model for the prediction of the molar volume effects accompanying changes in the primary coordination number of aqueous metal ions
A model for the prediction of the molar volume effects accompanying changes in the primary coordination number of aqueous metal ions
复制标题
预测伴随水溶液金属离子主配位数变化的摩尔体积效应的模型
DOI：
10.1021/ic00161a002
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发表时间：
1983
影响因子：
4.6
通讯作者：
T. Swaddle
中科院分区：
文献类型：
--
作者：
T. Swaddle
方程1与“绝对”偏摩尔体积绝压(在无限稀释,298 K和0.1 MPa,相对于绝压= -5.4立方厘米摩尔”1水的H + 14)水阳离子Mz +有效的离子radius15 r (pm) n。我们已经表明elsewhere8, 13 eq 1繁殖还有vab测量值为水Mz + n是已知的(例如,从核磁共振或x射线衍射的研究解决方案)在2立方厘米摩尔的1在几乎所有情况下,至少在许多zbbbb1离子数据的实验不确定度之内。结果表明，这种方法也可以令人满意地解释水金属阳离子之间电子转移的外球和内球替代途径的激活体积之间的差异。之前的模型。Stranks16认为，从ML“Z+在溶液中扫出的体积来看，ML”Z+的第一个配位“球体”可以近似为真实的球体，并且对于给定的M， L和Z，无论n是5还是6，这个体积（因此测量的ML“Z+的摩尔体积）应该是相同的。因此，对于解离激活过程
Equation 1 relates the “absolute” partial molar volume Pabs (at infinite dilution, 298 K and 0.1 MPa, relative to Pabs=-5.4 cm3 mol" 1 for aqueous H+ 14) of an aqueous cation Mz+ of effective ionic radius15 r (in pm) to n. We have shown elsewhere8, 13 that eq 1 reproduces measured Vabs values for aqueous Mz+ for which n is known (eg, from NMR or X-ray diffraction studies of solutions) to within 2 cm3 mol'1 in almost all cases, that is, to within the experimental uncertainty of the data for many ions of z> 1 at least. It transpires that this approach can also account satisfac-torily for the difference between the volumes of activation for outer-sphere and inner-sphere alternative pathways for electron transfer between aqueous metal cations. Previous Models. Stranks16 suggested that the first coor-dination “spheres” of species ML „Z+ could be approximated to real spheres from the point of view of the volume swept out by ML „Z+ in solution and that this volume (and hence the measured molar volume of ML „Z+) should be the same for given M, L, and z whether n were 5 or 6. Thus, for the dissociative activation process