Instituto de Química, Universidade Federal do Rio de Janeiro (UFRJ), Av. Athos da Silveira Ramos 149, 21941-909, Rio de Janeiro, Brazil.
Current Address: Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
Chemistry. 2019 Apr 5;25(20):5269-5279. doi: 10.1002/chem.201805991. Epub 2019 Mar 14.
Born-Oppenheimer molecular dynamics (BOMD) and periodic density functional theory (DFT) calculations have been applied for describing the mechanism of formation of lithium fluoride (LiF) nanotubes with cubic, hexagonal, octagonal, decagonal, dodecagonal, and tetradecagonal cross-sections. It has been shown that high energy structures, such as nanowires, nanorings, nanosheets, and nanopolyhedra are transient species for the formation of stable nanotubes. Unprecedented (LiF) clusters (n≤12) were also identified, some of them lying less than 10 kcal mol above their respective global minima. Such findings indicate that stochastic synthetic techniques, such as laser ablation and chemical vapor deposition, should be combined with a template-driven procedure in order to generate the nanotubes with adequate efficiency. Apart from the stepwise growth of LiF units, the formation of nanotubes was also studied by rolling up a planar square sheet monolayer, which could be hypothetically produced from the exfoliation of the FCC crystal structure. It was shown that both pathways could lead to the formation of alkali halide nanotubes, a still unprecedented set of one-dimensional materials.
Born-Oppenheimer 分子动力学 (BOMD) 和周期性密度泛函理论 (DFT) 计算已被应用于描述具有立方、六方、八面、十面、十二面和十四面横截面的氟化锂 (LiF) 纳米管形成机制。结果表明，高能结构，如纳米线、纳米环、纳米片和纳米多面体，是形成稳定纳米管的瞬态物种。还确定了前所未有的 (LiF) 团簇（n≤12），其中一些位于各自全局最小值之上不到 10 kcal/mol。这些发现表明，随机合成技术，如激光烧蚀和化学气相沉积，应与模板驱动程序相结合，以提高生成效率。除了 LiF 单元的逐步生长外，还通过卷起平面正方形单层来研究纳米管的形成，该单层可假设从 FCC 晶体结构的剥落中产生。结果表明，两种途径都可以形成碱金属卤化物纳米管，这是一组前所未有的一维材料。
