Metal-organic frameworks [M₂(2-I-bdc)₂bpe] (M = Zn(II) (1), Co(II) (2), 2-I-bdc = 2-iodoterephtalic acid, and bpe = 1,2-bis(4-pyridyl)ethane) were prepared and characterized by X-ray diffractometry. Both compounds retain their 3D structure after the removal of guest DMF molecules. Selectivity of sorption of different organic substrates from the gas phase was investigated for both complexes.

Five new coordination polymers based on Ln³⁺ and 2,5-diiodoterephthalates (2,5-I-bdc)— {[La₂(2,5-I-bdc)₃(DMF)₄]}·2DMF (1) and {[Ln₂(2,5-I-bdc)₃(DMF)₄]} (Ln = La (2), Nd (3), Sm (4) and Eu (5))—were prepared and characterized by single crystal and powder X-ray diffractometry. Luminescent behavior was examined (the highest quantum yield is 4.5%); thermal stability was examined using thermogravimetric analysis.

Two new coordination polymers based on Zn(II) and 2,5-diiodoterephthalate—{[Zn(2,5-I-bdc)bpe}] (1) and {[Zn(2,5-I-bdc)bpen}] (2)—were synthesized and characterized. Polymers 1 and 2 feature halogen bonding between the I atoms of MOF and DMF guest molecules, which plays a crucial role in structure stabilization. Selectivity of sorption towards different organic substrates was examined.

Three-dimensional coordination polymers Cat₂[{Zn₄O}₂(H₂O)₂(2,5-I-bdc)₇] (1) (2,5-I-bdc = 2,5-diiodoterephthalate, Cat is dimethylammonium) and [Zn₂(2,5-I-bdc)₂dabco] (2) (dabco is 1,4-diazobicyclo [2.2.2]octane) are prepared. The structures of 1 and 2 are determined by single crystal X-ray diffraction. It is shown that the structure of 2 has a halogen bond between guest DMF molecules and the MOF iodine atom. The I⋯O distances are 2.93-3.03 Å.

3D coordination polymers of Zn(II) with 2,5-diiodoterephthalate linkers (DMA)₂[Zn(2,5-I-bdc)₂]·1.5DMF (1) and K₂[Zn(2,5-I-bdc)₂]·2DMF (2) (2,5-I-bdc = 2,5-diiodoterephthalate) are prepared; their structure is established by XRD.