Figure 5. The X-ray diffraction (XRD) pattern of the new 2D carbon crystal.

(a) The XRD pattern of 4–6 carbophene has only one peak, indicating a few-layer structure. The position of diffraction angle in the 4–6 carbophene 2D carbon crystal is around 2θ = ~23°. (b) The XRD pattern of reduced graphene oxide (rGO). The position of diffraction angle of rGO is at 2θ = ~26°. In graphene the interlayer distance (d₀₀₂) is 0.343 nm for the AB-stack. The estimated interlayer distance in the new 2D carbon crystal is 0.387 nm. The smaller 2θ and larger d₀₀₂ may be caused by the distorted sp² hybrid orbitals of carbon atoms in the 4–6 carbophene crystal.