Structure and Layer Interaction in Carbon Monofluoride and Graphane: A Comparative Computational Study
Structure and Layer Interaction in Carbon Monofluoride and Graphane: A Comparative Computational Study
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DOI：
10.1021/jp1003566
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发表时间：
2010-04-29
影响因子：
2.9
通讯作者：
Chernozatonskii, Leonid A.
中科院分区：
文献类型：
--
作者：
Artyukhov, Vasilii I.;Chernozatonskii, Leonid A.
从实用的角度来看，单氟化碳（CF）和石墨烯是两种非常不同的材料，但这些材料的基本化学基序是密切相关的：两者都可以被描述为二维多环（氟-/氢-）碳。然而，关于这些材料结构的实际实验数据是模糊的（CF）或稀缺的（石墨烯）。在此，我们报告了（CF）和石墨烯结构的详细计算研究，包括单层结构和三维堆叠结构。实现层间相互作用的适当描述的关键是使用非局域密度泛函来描述从第一原理出发的远距离色散吸引。我们发现两种材料在构象能量学（包括先前研究中未考虑的“横摆椅”构象基序）和层堆叠安排方面具有很强的定性和定量相似性。（CF）的分子力学力场在再现我们的量子化学结果方面表现得非常好，并且适合非常通用的ops /AA分子力学框架。结合量子化学计算和经典分子动力学模拟的结果，利用新力场提出了一种途径来解释这些材料中观察到的过小的实验面内晶格常数值，以及（CF）中层间距离的变化，这是基于构象无序的共同基础。
Carbon monofluoride (CF) and graphane are two very different materials from the practical point of view, but the basic chemical motifs of these materials are closely related: both can be described as two-dimensional polycyclic (fluoro-/hydro-)carbons. However, the actual experimental data on the structure of these materials is ambiguous ((CF)) or scarce (graphane). Herein, we report a detailed computational study of structure of (CF) and graphane, both in a monolayer configuration and in three-dimensional stacked arrangements. A crucial point in achieving a proper description of layer interactions is the use of a nonlocal density functional to describe long-range dispersion attraction from first principles. We find strong qualitative and quantitative similarities between the two materials in both conformational energetics (including a "gauche-chair" conformational motif not considered in previous studies) and layer stacking arrangements. A molecular mechanics force field is derived for (CF) that performs exceptionally well at reproducing our quantum chemical results and fits into a very general OPLS/AA molecular mechanics framework. The combined results of quantum chemical calculations and classical molecular dynamics simulations using the new force field suggest a pathway to explain the too-small experimental in-plane lattice constant values observed in these materials, as well as the variation of interlayer distance in (CF), on the common basis of conformational disorder.