Strong halogen bond with guest molecules in Co(II) 2,5-diiodoterephthalate metal-organic framework

Two heteroleptic Co(II) 2,5-diiodoisoterephthalates (2,5-I-bdc) with 1,2-bis(4-pyridyl)ethane (bpe) linker, both of {[Co(2,5-I-bdc)bpe]·XDMF}n formulae (1 and 2), were prepared. In the structure of 2, guest DMF molecules form a prominent halogen bond with iodine atoms of dicarboxylate ligand. The energies of these interactons were estimated from the bond critical point characteristics (QTAIM analysis).