Effect of perturbing strata on chain conformations and ordering in closely packed layered structures of chain molecules
Effect of perturbing strata on chain conformations and ordering in closely packed layered structures of chain molecules
复制标题
扰动层对链构象和链分子紧密堆积层状结构排序的影响
DOI：
--
复制
发表时间：
1993
期刊：
影响因子：
--
通讯作者：
J. Eilers
中科院分区：
文献类型：
--
作者：
Y. Shnidman;Abraham Ulman;J. Eilers
堆积的烷基链的二维组件可以被视为微层或层的堆叠，其中每个层由紧密堆积的原子团组成，层之间具有链内键合约束。扰动层可以通过在一个层中施加与另一层的紧密堆积要求不相称的间距、对称性和尺寸约束来引入。利用分子力学和动力学模拟，我们研究了两个具体的例子：一个与平面密堆积不相容的化学吸附势和一个中链庞大基团。我们发现一个渐进的重排，从包装在扰动层朝着较低的能量包装，在成本的链，增加他们的总键角能量的渐进扭曲。这种重排的实验影响进行了简要讨论。
Two-dimensional assemblies of packed alkyl chains can be viewed as stacks of microlayers or strata, where each stratum is comprised of closely packed atomic groups with intrachain bonding constraints between the strata. A perturbing stratum can be introduced by imposing spacing, symmetry, and size constraints in one of the strata that are incommensurate with close-packing requirements of the other strata. Using molecular mechanics and dynamics simulations, we study two concrete examples: a chemisorption potential incompatible with planar close-packing and a mid-chain bulky group. We find a progressive rearrangement from the packing at the perturbing stratum toward a lower energy-packing, at the expense of progressive distortions of the chains that increase their total bond angle energy. The experimental implications of such rearrangements are discussed briefly.