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Ab initio study of C20 isomers: geometry and vibrational frequencies

✍ Scribed by Zhiqiang Wang; Paul Day; Ruth Pachter

Publisher: Elsevier Science
Year: 1996
Tongue: English
Weight: 361 KB
Volume: 248
Category: Article
ISSN: 0009-2614
DOI: 10.1016/0009-2614(95)01299-0

No coin nor oath required. For personal study only.

✦ Synopsis

Geometry optimizations are performed for three isomers of C2o, namely the ring, bowl (corannulene-like), and cage (fullerene-like) configurations, using both the local density functional approximation (LDA), and gradient-corrected density functional theory (BLYP). The BLYP results confirm the previous single point calculation based on Hartree-Fock geometries, which is in favor of the ring geometry, while the LDA results still indicate a reversed order of energy, thus favoring the cage geometry. Our calculated LDA vibrational spectra of the ring geometry show significant differences with those of HF in the widths of two band gaps. In addition, our M~ller-Plesset second-order perturbation theory (MP2) single point calculations using GAMESS show preference towards the bowl structure, which differs from previous similar calculations.

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