Early stages of phase selection in MOF formation observed in molecular Monte Carlo simulations.
Early stages of phase selection in MOF formation observed in molecular Monte Carlo simulations.
复制标题
作者：
金属有机骨架(MOF)由有机连接物桥联的金属节点组成，由于其具有客体特有的气体吸附、分离、药物输送和催化性能，因此显示出巨大的应用前景。原则上，金属节点、有机连接物和合成条件的选择提供了对结构和功能的工程化控制。对于MOF来说，要实现其潜力并成为不仅仅是有希望的材料，合成过程中一定程度的可预测性以及对自组装或初始生长过程的更好理解是至关重要的。以琥珀酸钴为例，我们提出了一种分子蒙特卡罗方法，它可以模拟MOF组装的早期阶段，它根据合成温度和配体与金属的比例呈现出不同的相。我们介绍了一种新的接触簇蒙特卡罗(CCMC)算法，它使用一个重叠的“虚拟中心”系统来表示钴以及金属-金属和金属-配体缔合的配位环境。我们的模拟捕捉到了实验观察到的琥珀酸钴在348K时的合成相差异，据我们所知，这是第一种情况下不同MOF相的形成作为组成的函数被无偏分子模拟捕捉到。CCMC算法同样适用于任何以短程吸引相互作用为主要特征的体系，包括氢键网络、金属-配体配位网络，或具有粘性斑块的粒子组装，如胶体体系或蛋白质复合体的形成。在金属 ： 配体比为(A)5 ： 1和(B)1 ： 1且具有相同相互作用势的金属MOF组装模拟中产生的团簇。
Metal–organic frameworks (MOF) comprising metal nodes bridged by organic linkers show great promise because of their guest-specific gas sorption, separation, drug-delivery, and catalytic properties. The selection of metal node, organic linker, and synthesis conditions in principle offers engineered control over both structure and function. For MOFs to realise their potential and to become more than just promising materials, a degree of predictability in the synthesis and a better understanding of the self-assembly or initial growth processes is of paramount importance. Using cobalt succinate, a MOF that exhibits a variety of phases depending on synthesis temperature and ligand to metal ratio, as proof of concept, we present a molecular Monte Carlo approach that allows us to simulate the early stage of MOF assembly. We introduce a new Contact Cluster Monte Carlo (CCMC) algorithm which uses a system of overlapping “virtual sites” to represent the coordination environment of the cobalt and both metal–metal and metal–ligand associations. Our simulations capture the experimentally observed synthesis phase distinction in cobalt succinate at 348 K. To the best of our knowledge this is the first case in which the formation of different MOF phases as a function of composition is captured by unbiased molecular simulations. The CCMC algorithm is equally applicable to any system in which short-range attractive interactions are a dominant feature, including hydrogen-bonding networks, metal–ligand coordination networks, or the assembly of particles with “sticky” patches, such as colloidal systems or the formation of protein complexes. Clusters produced in simulations of MOF assembly at metal : ligand ratios of (a) 5 : 1 and (b) 1 : 1 with identical interaction potentials.
登录
查看更多内容
影响因子：
3.3
作者：
Chen, B;Siepmann, JI
通讯作者：
Siepmann, JI
影响因子：
13.6
作者：
Henzler K;Fetisov EO;Galib M;Baer MD;Legg BA;Borca C;Xto JM;Pin S;Fulton JL;Schenter GK;Govind N;Siepmann JI;Mundy CJ;Huthwelker T;De Yoreo JJ
通讯作者：
De Yoreo JJ
影响因子：
17.1
作者：
Biswal, Debasmita;Kusalik, Peter G.
通讯作者：
Kusalik, Peter G.
影响因子：
2.1
作者：
Gupta, A;Chempath, S;Snurr, RQ
通讯作者：
Snurr, RQ
影响因子：
16.6
作者：
Forster, PM;Stock, N;Cheetham, AK
通讯作者：
Cheetham, AK