Large scale molecular dynamics simulations are used to investigate thestructural and dynamical modifications of supercooled water when confinedinside an hydrophilic nanopore. We then investigate the evolution of theauto-organization of the most and the least mobile molecules (dynamicalheterogeneity and string-like cooperative motions) when supercooled water isconfined. Our calculations use the recent TIP5P intermolecular potential forwater. We observe a strong slowing down of the dynamical properties when theliquid is confined, although the liquid structure is found to remain unchangedwhen corrected from the pore geometry. We then study cooperative motions insidesupercooled confined water in comparison with bulk water. We observe strongmodifications of the cooperative motions when the liquid is confined. Weobserve that dynamical heterogeneities and the associated correlation lengthsare strongly increased as well as string-like motions in the confined liquid.This result, which is in opposition with the expected limitation of thecorrelation length by the confinement procedure, may explain (or be explainedby) the slowing down of the dynamics. However the comparison of the dynamicalheterogeneities at constant diffusion coefficient shows that the slowing downof the dynamics is not sufficient to explain the increase of the correlationlengths.
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