[5]Paracyclophane: an important example of ring strain and aromaticity in hydrocarbon compounds
[5]Paracyclophane: an important example of ring strain and aromaticity in hydrocarbon compounds
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[5]对环芳烷：烃类化合物中环张力和芳香性的重要例子
DOI：
10.1021/ja00244a008
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发表时间：
1987
影响因子：
15
通讯作者：
H. Schaefer
中科院分区：
文献类型：
--
作者：
J. Rice;Timothy J. Lee;R. B. Remington;W. D. Allen;D. Clabo;H. Schaefer
用从头算分子量子力学方法研究了最近由Bickelhaupt等9位同事发现的[5]对环芳分子（CnH 14）。通过自洽场（SCF）方法，使用最小（STO-3G）和双（DZ）基组预测了完整的分子结构。临界几何参数是苯环平面性的偏差，并预测为22.4和23.7，分别与STO-3G和DZ基组。这两个角度显着小于经验和半经验计算方法预测。给出了DZ SCF的简谐振动频率和红外强度，并与苯的类似结果进行了比较.对环芳烷的最低三重态和第一激发单重态也被认为是在基态平衡几何。最后，根据合适的同连键反应估计共振能量，并与苯的类似预测进行比较。
Ab initio molecular quantum mechanical methods have been applied to the [5] paracyclophane molecule (CnH14), which has recently been preparedby Bickelhaupt and nine co-workers. The complete molecular structure has been predicted via the self-consistent-field (SCF) method, by using both minimum (STO-3G) and double-(DZ) basis sets. The critical geometrical parameter is the deviation of the benzene ring from planarity, and is predicted to be 22.4 and 23.7, respectively, with the STO-3G and DZ basis sets. Both angles are significantly less than those predicted with empirical and semiempirical computational methods. DZ SCF harmonic vibrational frequenciesand infrared intensities are presented and compared with similar results for benzene. The lowest triplet and first excited singlet states of [5] paracyclophane are also considered at the ground-state equilibrium geometry. Finally the resonance energy is estimated from a suitable homodesmotic reaction and compared to the analogous prediction for benzene.