  The reactivity of iron atoms, clusters and nanoparticles (nZVI) is of
increasing interest owing to their important practical applications, ranging
from the steel industry to water remediation technologies. Here, we provide an
overview of computational methods and models that can be applied to study nZVI
reactions and discuss their benefits and limitations. We also report current
progress in calculations through recent examples treating the reactivity of
nZVI particles. Finally, we consider the potential use of highly accurate
methods with favorable scaling (such as quantum Monte Carlo or random phase
approximation), which are currently considered too computationally expensive
but are expected to become more amenable in the future as computer power
increases.
