TY - JOUR
T1 - Evolution from surface-influenced to bulk-like dynamics in nanoscopically confined water
AU - Castrillón, Santiago Romero Vargas
AU - Giovambattista, Nicolás
AU - Aksay, Unan A.
AU - Debenedetti, Pablo G.
PY - 2009/6/11
Y1 - 2009/6/11
N2 - We use molecular dynamics simulations to study the influence of confinement on the dynamics of a nanoscopic water film at T = 300 K and p = 1.0 g cm -3. We consider two infinite hydrophilic (β-cristobalite) silica surfaces separated by distances between 0.6 and 5.0 nm. The width of the region characterized by surfacedominated slowing down of water rotational dynamics is ̃0.5 nm, while the corresponding width for translational dynamics is ̃1.0 nm. The different extent of perturbation undergone by the in-plane dynamic properties is evidence of rotational-translational decoupling. The local in-plane rotational relaxation time and translational diffusion coefficient collapse onto confinement-independent "master" profiles as long as the separation d > 1.0 nm. Long-time tails in the perpendicular component of the dipóle moment autocorrelation function are indicative of anisotropic behavior in the rotational relaxation.
AB - We use molecular dynamics simulations to study the influence of confinement on the dynamics of a nanoscopic water film at T = 300 K and p = 1.0 g cm -3. We consider two infinite hydrophilic (β-cristobalite) silica surfaces separated by distances between 0.6 and 5.0 nm. The width of the region characterized by surfacedominated slowing down of water rotational dynamics is ̃0.5 nm, while the corresponding width for translational dynamics is ̃1.0 nm. The different extent of perturbation undergone by the in-plane dynamic properties is evidence of rotational-translational decoupling. The local in-plane rotational relaxation time and translational diffusion coefficient collapse onto confinement-independent "master" profiles as long as the separation d > 1.0 nm. Long-time tails in the perpendicular component of the dipóle moment autocorrelation function are indicative of anisotropic behavior in the rotational relaxation.
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U2 - 10.1021/jp9025392
DO - 10.1021/jp9025392
M3 - Article
C2 - 19449830
AN - SCOPUS:67649373968
SN - 1520-6106
VL - 113
SP - 7973
EP - 7976
JO - Journal of Physical Chemistry B
JF - Journal of Physical Chemistry B
IS - 23
ER -