作者:Kwangyong Park、Tae-Won Lee、Min-Ju Yoon、Jong-In Choe
DOI:10.5012/bkcs.2014.35.2.531
日期:2014.2.20
The quantum mechanical properties of a series of oligo-para-phenylenes (2-11) were characterized using DFT B3LYP/6-311G(d,p) calculations. The global minimum among the various torsional conformers of an oligo-p-phenylene is calculated to be a twist conformation. A less stable planar conformation, in which all the dihedral angles in oligo-p-phenylene are restricted to be planar, has also been calculated. The total electronic energies, normal vibrational modes, Gibbs free energies, and HOMOs and LUMOs of the two different conformations (twisted and planar) of the oligo-p-phenylenes were analyzed. The energy differences between the HOMOs and LUMOs of the substrates are in accord with the maximum absorption peaks of the experimental UV spectra of 2-6. The calculated normal vibrational modes of 2-6 were comparable with their experimental IR spectra.
利用 DFT B3LYP/6-311G(d,p)计算表征了一系列低聚对苯二甲酸(2-11)的量子力学性质。根据计算,低聚对苯二甲苯的各种扭转构象中的全局最小构象为扭转构象。此外,还计算出了一种不太稳定的平面构象,即低聚对苯二甲酸丁二酯中的所有二面角都被限制为平面。分析了低聚对苯二甲苯两种不同构象(扭曲构象和平面构象)的总电子能量、正常振动模式、吉布斯自由能以及 HOMOs 和 LUMOs。底物的 HOMOs 和 LUMOs 之间的能量差异与 2-6 实验紫外光谱的最大吸收峰一致。计算得出的 2-6 的正常振动模式与其实验红外光谱相当。