D. Bedrov et al., Simulation and QENS studies of molecular dynamics in aqueous solutions of 1,2-dimethoxyethane, J PHYS CH B, 104(21), 2000, pp. 5151-5154
We compare the composition dependence of the self-diffusion coefficient of
water in aqueous solutions of 1,2-dimethoxyethane (DME) as obtained from in
coherent quasielastic neutron scattering measurements and molecular dynamic
s simulations. Simulations were performed using the TIP4P water model and a
quantum chemistry based potential for DME and DME/water interactions. Exce
llent agreement is seen between experiment and simulation, including the mi
nimum in the water self-diffusion coefficient at X-DME approximate to 0.2 p
redicted by our earlier simulations. Further, we investigated the influence
of the water potential on molecular dynamics in DME aqueous solutions by p
erforming simulations using the SPC, SPC/E, and MCY water models. The SPC a
nd MCY models yielded a water self-diffusion coefficient as a function of c
omposition in qualitative agreement with experiment, including the before m
entioned minimum. Quantitative agreement with experiment is poorer for thes
e potentials than for the TIP4P model. Surprisingly, simulations employing
the SPC/E model, known to provide the best description of self-diffusion in
pure water, showed a qualitatively incorrect dependence of water self-diff
usion on composition. The failure of the SPC/E water model was attributed t
o overestimation of the strength of water-water interactions.