Interaction between carbon dioxide and coal: atomic-scale characteristics and electronic structures

Geologic sequestration of CO$_{\mathrm{2}}$ in unmineable coal seams has been suggested to mitigate the effect of the increasing of the atmospheric CO$_{\mathrm{2}}$ concentration on global warming. Extensive experimental studies have been performed for the injection of CO$_{\mathrm{2}}$ into coalbeds. However, the atomic-level mechanism for the interaction between CO$_{\mathrm{2}}$ and coal has not been fully explored. We report first-principles density-functional calculations and \textit{ab initio} molecular dynamics simulations for the interaction between CO$_{\mathrm{2}}$ and the coal network. In particular, we report results about atomic-scale and electronic properties of the interaction. We also report a comparison with the interaction between CH$_{\mathrm{4}}$ and coal.