Scholarlink

<p>Endohedral metalloazafullerenes (EMAFs) and endohedral metalloborafullerenes (EMBFs) are nitrogen- and boron-doped carbon cages, respectively, with metallic species inside. Recent experiments have successfully synthesized U@C<sub>27</sub>B as the smallest EMBF. Herein, density functional theory (DFT) calculations were conducted to systematically investigate the possible structure of its corresponding EMAF analogue, U@C<sub>27</sub>N. By fully considering the relative energies at 0&#xa0;K and entropy effect at high temperatures for all potential U@C<sub>27</sub>N isomers, we predicted U@<i>T</i><sub><i>d</i></sub>-C<sub>27</sub>N-[5,5,5] and U@<i>T</i><sub><i>d</i></sub>-C<sub>27</sub>N-[5,5,6] with different nitrogen doping positions as its two major isomers. The encapsulated U atom formally adopts the highest VI oxidation state, and is effectively stabilized by the strong covalent interactions with the cage. Holding an unpaired electron on the cage, U@C<sub>27</sub>N could easily dimerize. Interestingly, it maintains a superatomic state with a perfect closed-shell 1S<sup>2</sup>1P<sup>6</sup>1D<sup>10</sup>1F<sup>14</sup> electronic configuration by using 32 out of 35 valence electrons in both the monomers and dimers. The novel structures and good stability promise the possible synthesis of this smallest EMAF in the experiments.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Structural Isomers and Superatomic Character of the Smallest Endohedral Azafullerene U@C27N

  • 期刊论文

  • 发表日期：

    2025年5月17日

查看全文
  • Zhenyao Shi,
  • Xinde Li,
  • Dongrun Sun,
  • Peng Jin

摘要

Endohedral metalloazafullerenes (EMAFs) and endohedral metalloborafullerenes (EMBFs) are nitrogen- and boron-doped carbon cages, respectively, with metallic species inside. Recent experiments have successfully synthesized U@C27B as the smallest EMBF. Herein, density functional theory (DFT) calculations were conducted to systematically investigate the possible structure of its corresponding EMAF analogue, U@C27N. By fully considering the relative energies at 0 K and entropy effect at high temperatures for all potential U@C27N isomers, we predicted U@Td-C27N-[5,5,5] and U@Td-C27N-[5,5,6] with different nitrogen doping positions as its two major isomers. The encapsulated U atom formally adopts the highest VI oxidation state, and is effectively stabilized by the strong covalent interactions with the cage. Holding an unpaired electron on the cage, U@C27N could easily dimerize. Interestingly, it maintains a superatomic state with a perfect closed-shell 1S21P61D101F14 electronic configuration by using 32 out of 35 valence electrons in both the monomers and dimers. The novel structures and good stability promise the possible synthesis of this smallest EMAF in the experiments.