This dataset contains data from two publications investigating mackinawite FeS in an aqueous environment. The first includes the derivation and validation of the force field parameters necessary to model the system (http://link.springer.com/article/10.1007/s00214-015-1782-8). In the second publication, the force field is employed to predict the structural and dynamical properties of water at the interface with the (001) surface of mackinawite (http://scitation.aip.org/content/aip/journal/jcp/144/9/10.1063/1.4942755).