Warning to Theoretical Structure Elucidation of Endohedral Metallofullerenes

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• 作者：Ruisheng Zhao ; Yijun Guo ; Pei Zhao ; Masahiro Ehara ; Shigeru Nagase ; Xiang Zhao
• 刊名：Journal of Physical Chemistry C
• 出版年：2016
• 出版时间：January 21, 2016
• 年：2016
• 卷：120
• 期：2
• 页码：1275-1283
• 全文大小：463K
• ISSN：1932-7455

文摘

Endohedral scandium fullerenes have attracted substantial interest since they were synthesized and isolated in 1992. The Sc₂C₇₄ series including both Sc₂@C₇₄ and Sc₂C₂@C₇₂ forms were thoroughly investigated with density functional theory (DFT) methods including B3LYP, CAM-B3LYP, M06-2X, wB97XD, and some other DFT methods combined with statistical mechanics in the present work. Among all the Sc₂C₇₄ isomers, Sc₂C₂@C_s(10528)-C₇₂ is the most thermodynamically stable one, and it is overwhelming at the temperature region of fullerene formation, which is very consistent with experiments. A deviation that the B3LYP method as well as other DFT methods without long-range corrections tends to overestimate energies of Sc₂C₂@C₇₂ series was exposed for the first time to our best knowledge, and this deviation may not only be restricted to the Sc₂C₂@C₇₂ series but also apply to other scandium carbide fullerenes Sc₂C₂@C_2n (2n ≠ 72) and even other metal carbide fullerenes. Misleading conclusions will be drawn on the basis of inaccurate energies calculated with B3LYP method and other DFT methods without long-range corrections. As B3LYP, BP86, PBE, etc. are fairly widely used methods in theoretical studies of endohedral metallofullerenes, our work is an instructive warning to these studies.