The crystal structures of metal-organic frameworks (MOFs) are typically determined by the strong chemical bonds formed between the organic and inorganic building units. However, the latest generation of redox-active frameworks often rely on counterions in the pores to access specific charge states of the components. Here, we model the crystal structures of three layered MOFs based on the redox-active ligand 2,5-dihydroxybenzoquinone (dhbq): Ti2(Cl2dhbq)3, V2(Cl2dhbq)3 and Fe2(Cl2dhbq)3 with implicit and explicit counterions. Our full-potential first-principles calculations indicate that while the reported hexagonal structure is readily obtained for Ti and V, the Fe framework is stabilised only by the presence of explicit counterions. For high counterion concentrations, we observe the formation of an electride-like pocket in the pore center. An outlook is provided on the implications of solvent and counterion control for engineering the structures and properties of porous solids.
Bibliographical noteFunding Information:
M.J.G. is funded by a studentship from the Royal Society. K.T. is funded by the Independent Research Fund Denmark through the International Postdoctoral grant (0164‐00015B). Via our membership of the UK's HEC Materials Chemistry Consortium, which is funded by EPSRC (EP/L000202), this work used the ARCHER2 UK National Supercomputing Service ( http://www.archer.ac.uk ). We are grateful to the UK Materials and Molecular Modelling Hub for computational resources, which is partially funded by EPSRC (EP/P020194/1). Spanish and Generalitat Valenciana governments are acknowledged (PID2020‐119748GA‐I00 funded by MICIN/AEI/10.13039/501100011033 and GV/2021/027).
© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.
- ab-initio calculations
- density functional theory
- hybrid materials
- materials science
- metal-organic frameworks