3.1 Structural Characteristics
The geometrical structures of superalkali OM3 doped GYs (GY, GDY, and GTY) were systematically investigated using density functional method. To search for the most stable structure of the resulting complexes, we considered all the possible interaction orientations between OM3 and GYs. The top and side views of the stable structures of the OM3@GYs (M = Li, Na, and K) complexes are displayed in Figure 3. In the case of OLi3@GY, the OLi3 unit is located above the central pore of GY and the three Li atoms are close to three –C≡C– units, respectively. ONa3@GY and OK3@GY possess similar geometric features, in which superalkali OM3 deviates from the central position of the pore and one of the Na/K atoms tends to approach one of the benzene rings. It can be seen that the GY