...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>The journal of physical chemistry, A. Molecules, spectroscopy, kinetics, environment, & general theory >Ultrafast Solvation Dynamics Reveal that Octa Acid Capsule's Interior Dryness Depends on the Guest
【24h】

Ultrafast Solvation Dynamics Reveal that Octa Acid Capsule's Interior Dryness Depends on the Guest

机译：超快溶剂化动力学显示，八藻酸胶囊的内部干燥取决于客人

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Coumarins are well-known to exhibit environment-dependent excited-state behavior. We have exploited this feature to probe the accessibility of solvent water molecules to coumarins (guest) encapsulated within an organic capsule (host). Two sets of coumarins, one small that fits well within the capsule and the other larger that fits within an enlarged capsule, are used as guests. In our study, the two sets of coumarins serve different purposes: one is employed to explore electron transfer across the capsule and the other to release photoprotected acids into the aqueous environment. The capsule is made up of two molecules of octa acid (OA) and is soluble in an aqueous medium under slightly basic conditions. Molecular modeling studies revealed that while the OA capsule is fully closed with no access to water in the case of smaller coumarins, with the larger molecules, the capsule is not tight and the guest is in contact with water molecules, the number being dependent on the size of the coumarin. We have used the ultrafast time-dependent Stokes shift method to understand the solvent dynamics around the above guest molecules encapsulated within an OA capsule in an aqueous medium. Results depict that for the smaller sets of coumarins, water cannot access the guests within the OA cavity during their excited state lifetime. However, the case is completely different for the larger coumaryl esters. Distorted capsule structure exposes the guest to water, and a dynamics Stokes shift is observed. The average solvation time decreases with the increasing size of guests that clearly indicates accessibility of the encapsulated guests toward greater number of water molecules as the capsule structure distorts with increasing size of the guests. Results of the ultrafast solvation dynamics are consistent with that of molecular dynamics simulation.
机译：香豆素众所周知，可以展示依赖环境兴奋状态行为。我们利用了该特征来探讨溶剂水分子的可达性与在有机胶囊（宿主）内封装的香豆素（客户）。两组香豆素，一个小的香豆素，适合在胶囊内，另一个较大的胶囊内的较大较大，用作客人。在我们的研究中，两组香豆素服务于不同的目的：一种用于探讨胶囊上的电子转移，另一个用于释放光印化酸进入水性环境中。胶囊由两个八藻酸（OA）分子组成，可溶于略微碱性条件下的水性介质。分子建模研究表明，虽然OA胶囊完全关闭，但在较小的香豆素的情况下没有进入水，但随着较大的分子，胶囊不紧，客人与水分子接触，这些数量取决于香豆素的大小。我们使用超快时间依赖的Stokes换档方法来了解围绕上述客体分子围绕含水介质中的OA胶囊内的客体分子的溶剂动力学。结果描述，对于较小的香豆素，水无法在兴奋状态寿命期间进入OA腔内的客人。然而，较大的香豆酰胺酯是完全不同的。扭曲的胶囊结构将客人视为水，并且观察到动力学斯托克斯转变。平均溶剂化时间随着越来越大的载体的较大尺寸而降低，这些客人清楚地表明封装的客人可以在胶囊结构随着客人的尺寸扭曲而扭曲的封装的客体朝向更多的水分子。超快溶剂化动力学的结果与分子动力学模拟的结果一致。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号