The ab initio neon–water potential-energy surface and its relationship with the hydrophobic hydration shell

Abstract

The neon–water system has been investigated by abinitio quantum-chemical calculations. The potential-energy surface (PES) for the 1:1 Ne–H₂O interaction has been scanned at the MP2(full) level, with the 6-311++G(3df,2pd) basis set augmented with bond functions located midway between Ne and O. The most stable neon–water arrangement has r = 320 pm, θ = 120°, with a counterpoise-corrected binding energy of −0.54 kJ mol⁻¹. The PES is otherwise quite flat (with binding energies of ca. −0.4 kJ mol⁻¹) for all θ values if r > ca. 310 pm. The off-plane, perpendicular approach is unfavourable. NMR shielding and the electric field gradient at all nuclei show only very small changes with respect to the isolated components.