极性分子键角与键偶极矩的关系

Relationship between the Bond Dipole Moment and Bond Angle of Polar Molecules

研究了基态极性分子的键角和键偶极矩之间的关系。我们采用原子偶极矩校正的Hirshfeld(ADCH)电荷来计算键偶极矩,利用电子的局域函数和键临界点处的局域函数值来分析键的电子结构。通过对IVA族(IVA=C,Si,Ge)、VA族(VA=N,P,As)、VIA族(VIA=O,S,Se)和VIIA族(VIIA=F,Cl,Br)元素形成的系列共价型基态分子,以及环状基态分子的键角和键偶极矩数据进行分析,发现在键的电子结构类似的情况下,由于键偶极矩的排斥作用,这些分子的键角随键偶极矩的增加而增大。这一发现有助于加深我们对分子几何结构的认识。

The relationship between the bond angle and bond dipole moment is investigated. The atomic dipole moment corrected Hirshfeld（ADCH） charges are used to calculate the bond dipole moment. The electron localization function and its values at the bond critical points are exploited to analyze the bond′s electronic structures. Through analyzing the data of a series of covalent compounds formed by the IVA（IVA = C, Si, Ge）,VA（VA = N, P, As）, VIA（VIA = O, S, Se） and VIIA（VIIA = F, Cl, Br） group elements, it is found that, owing to the repulsion of bond dipole moments, the bond angles of these molecules become larger as their corresponding bond dipole moments increase if the bonds′ electronic structures are similar. This observation is also true for the ring molecules studied here, although a stress exists within the ring.