Fig. 5: Molecular dynamics simulation.

a Molecular structures of tetra-PCL-OH and tetra-PCL-UPy. b Sandwich models for computing the interactions between tetra-PCL-OH or tetra-PCL-UPy and water molecules, where cyan lines represent the hydrogen bonds formed in the simulation system. c Free volume in NRC and NCC (see the space occupied by translucent light green volume) detected by a theoretical probe with a radius of 1 Å. Simulated pore size distributions (d) and fractional free volume (e) of NRC and NCC. f Areal density of the interaction energy between tetra-PCL-OH or tetra-PCL-UPy and water molecules. g Areal density of hydrogen bonds formed between tetra-PCL-OH or tetra-PCL-UPy and water molecules.