Stability and electronic, phononic, thermal and optical properties of SrX (X = S, Se) nanosheets based on AIMD and DFT computations.

We study the electronic structure, stability, and thermal and optical properties of hexagonal SrS and SrSe monolayers using first-principles calculations. PBEsol generally improves the calculated equilibrium properties of solids and their surfaces, predicting a wider band gap of the monolayers, which is closer to the results obtained with HSE06. Phonon dispersion relations and the molecular dynamics (AIMD) method confirm the dynamic and thermal stability of both structures.

Computer simulations of the diffusion of Na and Cl ions across POPC lipid bilayer membranes.

We have carried out molecular dynamics simulations using NAMD to study the diffusivity of Na and Cl ions across a POPC lipid bilayer membrane. We show that an imbalance of positively and negatively charged ions on either side of the membrane leads to the diffusion of ions and water molecules. We considered the cases of both weak and very strong charge imbalance across the membrane.