  In this work we examine the nucleation from NaCl aqueous solutions within
nano-confined environments, employing enhanced sampling molecular dynamics
simulations integrated with machine learning-derived reaction coordinates.
Through our simulations, we successfully induce phase transitions between
solid, liquid, and a hydrated phase, typically observed at lower temperatures
in bulk environments. Interestingly, nano-confinement serves to stabilize the
solid phase and elevate melting points. Our simulations explain these findings
by underscoring the significant role of water, alongside ion aggregation and
subtle, anistropic dielectric behavior, in driving nucleation within
nano-constrained environments. This letter thus provides a framework for
sampling, analyzing and understanding nucleation processes under
nano-confinement.
