...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Macromolecular theory and simulations >Internal rotation of ester linkage in phenyl benzoate and hydroxybenzoic acid dimer as models of aromatic polyesters using density functional theory
【24h】

Internal rotation of ester linkage in phenyl benzoate and hydroxybenzoic acid dimer as models of aromatic polyesters using density functional theory

机译：苯酚酸酯和羟基苯甲酸二聚体中酯键的内旋作为芳香族聚酯模型的密度泛函理论

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

The internal rotation of the ester linkage was reinvestigated more quantitatively by using the density functional theory (DFT) in order to understand the characteristic stiffness and extendedness of polymer chain found in aromatic polyesters. Phenyl benzoate (PB) and p-hydroxybenzoic acid (HBA) dimer (HB) were selected as models of aromatic polyesters. The relaxed potential energy surface (PES) scan was carried out along the internal rotation of three bonds (denoted as R, S and T, respectively) of the aromatic esters by using the hybrid DFT (B3LYP) with 6-31G* basis set. The rotation of S bond, which mainly determines the linearity of the molecule, leads to the trans- and cis-conformers of PB. Since the cis-conformer of PB is 7.69 kcal . mol(-1) higher than the trans-conformer, the cis-conformer has little population at standard condition. HE does not have the cis-conformer. In addition, the chain persistence length of 364 Angstrom is obtained by the rotation matrix formalism using the structural parameters of HE. These agree with the experimental tal understanding that poly(p-hydroxybenzoic acid) is the class of stiff and extended polymer. [References: 28]
机译：为了了解芳族聚酯中聚合物链的特征刚度和延伸性，使用密度泛函理论（DFT）对酯键的内旋进行了更定量的研究。选择苯甲酸苯酯（PB）和对羟基苯甲酸（HBA）二聚体（HB）作为芳香族聚酯的模型。使用具有6-31G *基数的杂化DFT（B3LYP），沿着芳族酯的三个键（分别表示为R，S和T）的内旋进行弛豫势能面（PES）扫描。 S键的旋转主要决定分子的线性，导致PB的反式和顺式构象。由于PB的顺式构象异构体为7.69kcal。 mol（-1）比反式构象异构体高，顺式构象异构体在标准条件下几乎不存在。他没有顺式异构体。另外，使用HE的结构参数通过旋转矩阵形式主义获得了364埃的链持久性长度。这些符合实验的理解，即聚（对羟基苯甲酸）是刚性和延伸聚合物的一类。 [参考：28]

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