Potentials of classical force fields for interactions between Na<sup>+</sup> and carbon nanotubes<xref rid="cpb_27_9_098801_fn1" ref-type="fn">*</xref><fn id="cpb_27_9_098801_fn1"><label>*</label><p>Project supported by the National Science Fund for Outstanding Young Scholars of China (Grant No. 11722548) and the National Natural Science Foundation of China (Grant Nos. 11574339 and 11404361).</p></fn>

Potentials of classical force fields for interactions between Na⁺ and carbon nanotubes**

Project supported by the National Science Fund for Outstanding Young Scholars of China (Grant No. 11722548) and the National Natural Science Foundation of China (Grant Nos. 11574339 and 11404361).

Li De-Yuan^{1, 2}, Shi Guo-Sheng^{1, 2, †}, Hong Feng^{1, ‡}, Fang Hai-Ping^{1, 2}

(color online) (a), (d) Top views and (b), (e) side views of Na⁺/hydrated Na⁺, respectively, in the most stable geometric structures in the center of a (7,7)-type CNT. (c) and (f) Side views of the most stable geometric structures of the Na⁺ and hydrated Na⁺, respectively, at the entrance of a (7,7)-type CNT. In panel (b), the different adsorption sites are shown, i.e., above the hollow (H), C–C bond (B), and carbon atom top (T) sites of the hexagonal ring.