Weng Tingting, Schmidt J R
Theoretical Chemistry and Department of Chemistry , University of Wisconsin-Madison , Madison , Wisconin , 53706 , United States.
J Phys Chem A. 2019 Apr 4;123(13):3000-3012. doi: 10.1021/acs.jpca.8b12311. Epub 2019 Mar 15.
We have developed a transferable ab initio intramolecular force field for zeolitic imidazolate frameworks (ZIFs), "ZIF-FF", that is capable of quantitatively describing the structural properties and relative stabilities of ZIFs. In contrast to nearly all prior force fields, ZIF-FF properly describes the relative stability of ZIF polymorphs, a crucial element in ZIF nucleation and crystal growth. Beginning with a general Amber force field (GAFF), Zn-related force field parameters were optimized against dispersion-corrected DFT-calculated properties using a genetic algorithm. We validated the resulting force field by examining bond and angle distributions, phonon density of states, mechanical properties, diffusion properties and via modeling a ZIF amorphization process. Furthermore, we find that ZIF-FF is transferable, successfully describing relative stability of various ZIF surface structures, as well as the densities of ZIFs with diverse functionalized linkers.
我们已经为沸石咪唑酯骨架（ZIFs）开发了一种可转移的从头算分子内力场“ZIF-FF”，它能够定量描述ZIFs的结构性质和相对稳定性。与几乎所有先前的力场不同，ZIF-FF正确地描述了ZIF多晶型物的相对稳定性，这是ZIF成核和晶体生长中的关键因素。从通用的Amber力场（GAFF）开始，使用遗传算法针对色散校正的DFT计算属性优化了与锌相关的力场参数。我们通过检查键和角度分布、声子态密度、力学性能、扩散性能以及通过模拟ZIF非晶化过程来验证所得的力场。此外，我们发现ZIF-FF是可转移的，成功地描述了各种ZIF表面结构的相对稳定性，以及具有不同功能化连接体的ZIFs的密度。
