采用密度泛函理论B3LYP/6-31G*方法对C14H3中性和阳离子所有可能的构型、振动频率及热力学稳定性进行研究.基于目前的计算结果,C14H3和C14H3+最稳定的构型都是具有Cn对称的十四元环构型.如果构型里具有单叁键相互交替的聚炔烃结构,这个异构体就具有≈ 20cm-1的低频振动.C14通过加氢反应可以减小环内张力,使得十四元环能量降低,结构变得更加稳定.C14H3在温度低于1556K存在的可能性较大.%Density functional theory B3LYP with 6-31G+ basis set has been used to investigate the geometries,vibrational frequencies and thermodynamic stability of possible structures of C14 H3 radical and C14 H3+ cation. The result shows that the most stable structure of C14H3 radical and C14H3+ cation is fourteen-membered ring structure with C, symmetry. The low frequency origins in 20cm-1 of CI4H3 and C14H3+ which shows polyacetylenic structure. Furthermore,the internal tension was reduced after hydrogenation of C14 cycle compounds,so degraded the energy. As a result,it is possible that C14H3 is stable below 1556K.
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