Figure 2
From: Electronic and optical properties of the buckled and puckered phases of phosphorene and arsenene

(a) Top and side views of blue (buckled) phosphorene, (b) Top and side views of black (puckered) phosphorene. 1 and 2 correspond to the bond lengths, α and β correspond to bond angles of Table 1. Figure generated by using the open-source GIMP (GNU Image Manipulation Program) version 2.8.22 (URL: https://www.gimp.org/).