Scheme 2. Clusters of Atoms for Which Ground-State Energies, Spin Densities, and Hyperfine Coupling Constants Were Calculated.

Clusters represent simplified models of the 3Fe, 2Fe1Al, 1Fe2Al, and 3Al trimers that are expected to be found in MIL-100(Al,Fe). (Fe, orange; Al, blue; O, red; C, brown; H, white; for better distinction between the coordinated H₂O molecules and bonded OH^– groups, oxygen atoms of the latter are presented in violet).