We study by Monte Carlo simulations a coarse-grained model of a water layer confined in a fixed disordered matrix of hydrophobic nanoparticles at different particle concentrations c. For c=0 (bulk water) we find a first order liquid-liquid phase transition (LLPT). For c>0 our simulations are consistent with a LLPT line ending in two critical points at low and high pressure P. For c=25% we find a dramatic decrease of compressibility K_T, thermal expansion coefficient \alpha_P, specific heat C_P at high P and low temperature T. Surprisingly, the effect is present also for c as low as 2.4%. We conclude that the higher the confinement, the lower the thermodynamic fluctuations and the more difficult it will be to detect the LLPT.
@article{arxiv.1010.0693,
title = {Large decrease of fluctuations for supercooled water in hydrophobic nanoconfinement},
author = {Elena G. Strekalova and Marco G. Mazza and H. Eugene Stanley and Giancarlo Franzese},
journal= {arXiv preprint arXiv:1010.0693},
year = {2015}
}