Polyhedral Fluorocarbon (CF)n―Structures and Energies
Polyhedral Fluorocarbon (CF)n―Structures and Energies
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多面体氟碳化合物 (CF)n―结构和能量
DOI：
10.1021/jp900278d
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发表时间：
2009
影响因子：
3.7
通讯作者：
H. Jiao
中科院分区：
文献类型：
--
作者：
J. Jia;Chao Liu;Hai;P. Schleyer;H. Jiao
The structures and energies of selected (CX)n (n = even, 6−60, X = F or H) polyhedra, computed at the B3LYP/6-311++G(d,p)//B3LYP/6-31G(d,p) level, show (CH)n isomers to be generally less strained than the corresponding (CF)n analogues. For n = 6−24, both (CH)n and (CF)n favor the same geometric patterns. The tube isomers (t-(CX)n) of large (n = 26−60) species with fused five-membered rings at the tube ends are thermodynamically more stable than the cage isomers (c-(CX)n), deduced from the most stable carbon cages. The stabilities of tube isomers are determined by the distortion of the bond angles (angle strain) and the nonbonded F···F repulsive interactions. The latter have been quantified by means of homodesmotic equations. Four structural types of t-(CX)n structures are built on the basis of the number of fused five-membered rings, and the thermodynamically more stable t-(CX)n structures have more fused five-membered rings, in opposition to the isolated pentagon rule governing the stability of carbon fu...
