Molecular dynamics study of diffusion of formaldehyde in ice

We report a Molecular Dynamics simulation study of the diffusion process of formaldehyde (CH2O) in proton-disordered ice Ih at atmospheric pressure, in the temperature range 200–273 K. CH2O molecules diffuse in ice predominantly by jumping between B sites (bond-breaking mechanism), but substitutional diffusion can also be observed. At 260 K, the diffusion constant is predicted to be 4 × 10−7 cm2/s with the TIP4P–Ew water model, and 3 × 10−7 cm2/s with the TIP4P/Ice water model.