• 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 >Characterizing complexes with pnicogen bonds involving sp~2 hybridized phosphorus atoms: (H_2C=PX)_2 with X = F, Cl, OH, CN, NC, CCH, H, CH_3, and BH_2
【24h】

Characterizing complexes with pnicogen bonds involving sp~2 hybridized phosphorus atoms: (H_2C=PX)_2 with X = F, Cl, OH, CN, NC, CCH, H, CH_3, and BH_2

机译：表征带有p〜2杂化磷原子的光致原键的配合物：（H_2C = PX）_2，X = F，Cl，OH，CN，NC，CCH，H，CH_3和BH_2

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

Ab initio MP2/aug′-cc-pVTZ searches of the potential surfaces of (H_2C=PX)_2 complexes, with X = F, Cl, OH, CN, NC, CCH, H, CH_3, and BH_2, have been carried out to identify and characterize the properties of complexes with P~(···)P pnicogen bonds. All (H_2C=PX)_2 form equilibrium conformation A dimers with C_(2h) symmetry in which A- P~(···)P-A approaches a linear alignment, with A the atom of X directly bonded to P. Conformation A dimers containing the more electronegative substituents are stabilized by a P~(···)P pnicogen bond, have shorter P-P distances, and have binding energies which correlate with the P-P distance. Dimers stabilized by a P~(···)P pnicogen bond and two P~(···)H_b interactions consist of those with the more electropositive substituents, have shorter P-Hb distances, and have binding energies which are too high for their P-P distances. Conformation A complexes with P~(···)H_b interactions in addition to the P~(···)P bond are more stable than the corresponding (PH_2X)_2 complexes, while with only one exception, complexes stabilized by only a P~(···)P bond are less stable than the corresponding (PH_2X)_2 complexes. In the region of the potential surfaces with C-P~(···)P-C approaching linearity (conformation B), the only planar equilibrium complex is (H_2C=POH)_2, which is stabilized primarily by two O-H~(···)P hydrogen bonds. The remaining (H _2C=PX)_2 complexes are not stabilized by pnicogen bonds, but by π interactions between the two H_2C=PX monomers which are in parallel planes. When A-P~(···)P-C approaches linearity, two types of equilibrium structures with P~(···)P bonds exist. Of the conformation C dimers, (H_2C=POH)_2 is planar and the most stable, with a P~(···)P pnicogen bond and an O-H~(···)P hydrogen bond. (H_2C=PH)_2 and (H_2C=PCH_3)_2 are also planar, and stabilized by a P~(···)P pnicogen bond and a P~(···)H _b interaction. The absence of a P~(···)H _b interaction results in nonplanar C′ conformations with structures in which the monomers essentially retain their symmetry plane, but the plane of one molecule is rotated about the P~(···)P bond relative to the other. C and C′ dimers are less stable than the corresponding A dimers, except for (H_2C=PCH_3)_2. ~(31)P chemical shielding patterns are consistent with the changing nature of the interactions which stabilize (H_2C=PX)_2 complexes. EOM-CCSD ~(31)P-~(31)P spin-spin coupling constants increase quadratically as the P-P distance decreases.
机译：已对（H_2C = PX）_2配合物的潜在表面进行了从头开始的MP2 / aug'-cc-pVTZ搜索，其中X = F，Cl，OH，CN，NC，CCH，H，CH_3和BH_2鉴定和表征具有P〜（··）P致烟剂键的配合物的性质。所有（H_2C = PX）_2形成具有C_（2h）对称性的平衡构象A，其中A- P〜（··）PA接近线性排列，其中A的X原子直接键合到P。带有更多负电性的取代基通过P〜（···）P致烟剂键稳定，具有更短的PP距离，并具有与PP距离相关的结合能。通过P〜（···）P发烟性键和两个P〜（···）H_b相互作用稳定的二聚体由具有更多正电取代基，P-Hb距离更短，结合能太高的二聚体组成他们的PP距离。除了P〜（···）P键外，具有P〜（···）H_b相互作用的构象A配合物比相应的（PH_2X）_2配合物更稳定，而只有一个例外，该配合物仅由P稳定〜（···）P键不如相应的（PH_2X）_2配合物稳定。在CP〜（··）PC接近线性的势能面区域（结构B），唯一的平面平衡络合物是（H_2C = POH）_2，其主要由两个OH〜（···）P稳定氢键。其余的（H _2C = PX）_2配合物不是由成药原键稳定的，而是由平行平面中的两个H_2C = PX单体之间的π相互作用稳定的。当A-P〜（···）P-C接近线性时，存在两种具有P〜（···）P键的平衡结构。在构象C二聚体中，（H_2C = POH）_2是平面的，并且最稳定，具有P〜（··）P致烟剂键和O-H〜（···）P氢键。 （H_2C = PH）_2和（H_2C = PCH_3）_2也是平面的，并通过P〜（··）P致烟剂键和P〜（···）H _b相互作用稳定。没有P〜（···）H _b相互作用会导致非平面C'构象，其结构中的单体基本保持其对称平面，但一个分子的平面绕P〜（···）P旋转相对于另一个。除了（H_2C = PCH_3）_2外，C和C'二聚体比相应的A二聚体不稳定。 〜（31）P化学屏蔽模式与稳定（H_2C = PX）_2配合物的相互作用的变化性质一致。 EOM-CCSD〜（31）P-〜（31）P自旋-自旋耦合常数随着P-P距离的减小而平方增加。

著录项

相似文献

  • 外文文献
  • 中文文献
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