We present a sequential QM/MM study of the gas-liquid chemical shifts of water. Extensive quantum chemical calculations using density functional theory have been performed for structures of liquid water generated by Monte Carlo and Molecular Dynamic simulations. The dependence of the chemical shifts on the empirical potential used in the simulations, on the cluster size and on the functional chosen for the quantum chemical calculations were analyzed. The results after correcting for basis set superposition errors are in good agreement with the experimental data, showing that a simple empirical potential associated to an appropriate functional is able to describe the chemical shifts. All results presented here are statistically converged.
sequential QM/MM; water; NMR; chemical shift; DFT
