The Atoms-in-Molecules (AIM) approach was applied to clearly determine the complex hydrogen bonding pattern around the vanadate. The electron density, ρ, at the bond critical points showing the hydrogen bonding, and the strong hydrogen bond between H6 or H7 and water molecules above vanadate can be noted (e.g., 4: ρ(O16-H7)=0.03891, ρ (O15-H6)=0.06006; 5: