Fig. 5: Noncovalent interaction gradient isosurfaces of 1,4-dioxane in different conformations.

a The chair conformation. b The half-chair conformation. Carbon and oxygen are in green and red, respectively. Hydrogen is not displayed for clarity. The gradient isosurfaces show the intramolecular interactions using a blue–red scale with blue indicating strong attractions and red indicating strong repulsions. All conformations shown here were obtained directly (no energy minimization) from Simulation 30 of the 100 6320-ns simulations at 298 K. The isosurfaces in panels a and b show stronger intramolecular repulsion in the half-chair conformation than that of the chair conformation.