| Abstract
| - Present study combines NMR relaxation and line shape analysis for heavy water in the lamellar liquid crystallinephase of DDAO/2H2O. NMR spin−lattice, spin−spin relaxation times and the quadrupole splitting are measuredat two temperatures and three different water contents in the hydration regime. A molecular picture of waterhydration of the DDAO/2H2O interface is extracted, which indicates a much more rapid water translationaldiffusion along the detergent interface, as compared to phospholipid interfaces. The local order and dynamicsof the bound water are, however, not changing much between the two interfaces. This indicates that localinteractions of water with the headgroup are not much dependent on the actual phase or detergent system.This work also presents clear experimental evidence for a dip at the magic angle of the 2H powder spectrum,as theoretically predicted. Raising the temperature removes this observed dip at the isotropic frequency. Thiscorresponds to an increase in the correlation time τc from 8.5 ns at 25 °C to 20 ns at 55 °C, where τc isrelated to translational dynamics of water along the detergent/water interface. However, this counter-intuitiveincrease in τc with temperature may be interpreted as a reorganization of water at the interface, as is furthersupported by increasing quadrupolar splittings with increasing temperature.
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