Now, we have investigated the water monomer binding energy with different methods, and the results are represented in Figure . We have tried three different configurations; i) oxygen atom oriented towards the surface, ii) hydrogen atoms oriented towards the surface, and iii) both oxygen and hydrogen atoms parallel to the surface, as shown in Figure . Water is consistently found to be adsorbed in the parallel configuration. This is in agreement with the previous theoretical results obtained by Zhou et al. However, the strength of adsorption varies significantly across the methods (0.04-0.6 eV). It can be seen that D2, D3 methods, when used with both PBE and RPBE functionals, significantly improve the monomer binding energies, which is followed by optPBE (0.38 eV), optB88 (0.43 eV), and optB86b (0.46 eV) methods with reference to the experimentally measured heat of water adsorption of 0.56 eV. The lowest binding energy observed for RPBE functional can be correlated with the highest Pt-O bond length of 2.82Å. The higher accuracy of PBE-D3 in predicting water monomer binding energy compared to PBE-D2, which overestimates the Pt-H2O interaction, could be explained by the many-body term involved in the latter. An investigation into the electronic structure-based nature of the interaction has been carried out by taking PBE and PBE-D2 methods as these methods exhibit the highest disparity between the water monomer binding energies (Figure ) for the same exchange functional. This disparity can be expected to be originating from the Pt-H2O bond length differences of 0.35 Å between these methods. To examine the role of electronic structure in this metal-water interaction, we have conducted density of states (DOS) analysis. The density of states of H2O in the gas phase and H2O interacting with Pt(111) surface projected along O-p orbitals at PBE and PBE-D2 level are