THE INTRAMOLECULAR OH BOND-LENGTH OF WATER IN A CONCENTRATED POLY(ETHYLENEOXIDE) SOLUTION - AN NMR RELAXATION STUDY

The proton relaxation rates of normal as well as O-17-enriched water a nd the deuterium relaxation rate in H-2-enriched water were measured i n 10 monomolal poly(ethyleneoxide) solutions. The O-17-H-1 intramolecu lar dipolar contribution to the proton relaxation rate was determined. From these experimental parameters the intramolecular OH-bond distanc e in the water molecule was calculated. It was found that this distanc e is increased by a small (1%) but significant amount compared to the pure water value. The results indicate that the solvent shows increase d hydrogen bonding at the hydrophilic as well as the hydrophobic inter face.