On the structure and vibrational frequencies of C24
✍ Scribed by Jan M.L. Martin; Jamal El-Yazal; Jean-Pierre François
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 554 KB
- Volume
- 255
- Category
- Article
- ISSN
- 0009-2614
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✦ Synopsis
Several structures of C24 have been studied using different density functional methods. Using the B3LYP (Becke 3parameter Lee-Yang-Parr) method, fingerprint-quality infrared spectra have been computed for all species. The computed geometries differ substantially from those obtained at the SCF level due to delocalization effects. Both "exact-exchange" corrections to the exchange functional and the use of different correlation functionals have significant effects on the relative energetics. Our best calculations indicate that a dodecadehydrocoronene planar sheet and a fullerene cage are comparable in energy, followed by a polyacetylenic ring and a bowl structure. At high temperatures, the ring is expected to prevail due to vibrational entropy from many low-lying vibrations.
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