Theoretical calculations have been carried out using ab initio MP2 and B3LYP density functional methods to investigate the interaction between fluorinated dimethyl ethers (n(F) = 1-5) and water. Depending on the number of F atoms implanted on the dimethyl ethers, linear structures stabilized by intermolecular OwHw center dot center dot center dot O or CH center dot center dot center dot O-w hydrogen bonds or closed structures involving both hydrogen, bonds are formed. Binding energies of the hydrogen-bonded complexes range between 4 and 12 kJ mol(-1). Blue shifts of the CH stretching vibrations are predicted even in the absence of a direct CH center dot center dot center dot O interaction. The red shifts of the OH stretching vibrations of water in the open and closed structures are analyzed as well. The natural bond orbital analysis includes the sigma*(OwHw) and sigma*(CH) occupation, the hybridization of the C atom, the atomic charges, and the intra- and intermolecular hyperconjugation energies. These parameters are discussed as a function of the proton affinity (PA) of the O atom and the deprotonation enthalpy (DPE) of the CH bonds of the fluorinated ethers calculated in a previous work.(16) Our results show that the effective PA in determining the intermolecular O -> sigma*(OwHw) hyperconjugation energies decreases with increasing acidity of the CH bond. In turn, the effective acidity of the CH bond in determining the intermolecular O-w -> sigma*(CH) hyperconjugation energies decreases with increasing basicity of the O atom.