Theoretical Study of Amorphous Ice with Very High Methane Capacity

This work presents amorphous solid water structures containing exceptionally large amounts of methane, which could be used as a theoretical basis for a new methane storage method. Based on molecular dynamics and lattice dynamics methods, this study has demonstrated the stability of these structures over a wide range of thermodynamic parameters. Structural features have been investigated by calculating the number of hydrogen bonds and order parameters. The work shows the temperature dependencies of structural, dynamic, and energy characteristics at different methane contents. These characteristics, as well as the diffusion coefficient and methane content, have been compared with those of gas hydrates. The work demonstrates the possibility of storing up to 20–40 wt % of methane depending on the temperature.