Fig. 4
From: Direction-specific interaction forces underlying zinc oxide crystal growth by oriented attachment
Calculated PMF curves and energy barriers for ZnO(0001)–ZnO(000\(\bar 1\)) interactions at different azimuthal angles. a PMF curves at different azimuthal angles. An exemplary configuration at the first energy well is also shown. b Adhesion-free energies between ZnO particle and the substrate by using global minima (black filled circles) and second minima (red filled circles), at different angles. For better comparison with the adhesion-free energies estimated from experiments as shown in Fig. 3d, the free energies obtained from a are normalized to the surface area and the unit of J m−2 is used. c Energy barriers for moving the particle out of the lowest energy minima at different angles. d Comparison of contributions to the total PMF from particle–particle (P–P) interactions and from the water-mediated forces at 90°, 105°, and 120°. The total PMF and the P–P interaction contribution are calculated from MD simulations, and the water contribution is obtained as a difference between the previous two terms as shown in the inset
