fig4

Figure 4. Topographic images of different oriented C₆₀ assembled layers with a K-doped C₆₀ molecule. (A) STM image of a K-doped C₆₀ molecule surrounded by various oriented C₆₀ molecules. Image size is 8 × 8 nm² with U_B: +1.0 V and I_T: 50 pA. Yellow colored circles, dashed short lines and triangles, represent different oriented C₆₀ molecules; (B and C) High-resolution STM image of a K-doped C₆₀ molecule and the proposed structure with K atom replaced C and faced up; (D-G) Images of four different oriented C₆₀, overlapped with the corresponding structure models; Image size is 1.5 × 1.5 nm² with U_B: +1.0 V and I_T: 50 pA; (D) Round ball shape, suggests a rolling C₆₀; (E and F) Two-lobe shape, suggests H:H configuration; (G) Clover shape, suggests the H configuration. The triangles are arranged in a chiral 2×2 configuration, indicated by red rhombus, as reported previously^[19]. C₆₀: Fullerene; STM: scanning tunneling microscopy.