Fig. 4

Six representative high-symmetry configurations for H₂O molecules on phosphorene. a, b Along armchair direction, c, d along zigzag direction, and e, f along diagonal direction, and the total energy difference is a 0.104 eV molecule⁻¹, b 0.098 eV molecule⁻¹, c 0.275 eV molecule⁻¹, d 0 eV molecule⁻¹, e 0.123 eV molecule⁻¹, and f 0.150 eV molecule⁻¹, respectively