Coordination polymers may be obtained by assembling of suitable pre-synthesized metal-containing building blocks and linking organic ligands giving rise to a family of clusters based polymers. Metal clusters introduce their inherent extraordinary physical properties to the polymeric frameworks thus can make them more stable and therefore more promising for practical applications as well may lead to the more pronounced magnetic effects and porous structures. Homotrinuclear manganese and iron carboxylate clusters of composition [Mn3O(Piv)6(hmta)3]·PrOH (1) (Fig. 1) and [Fe3O(Piv)6(H2O)3]Piv ·2HPiv, where hmta = hexamethylenetetramine and HPiv = pivalic acid, have been used for the synthesis of heterometallic 1-D coordination polymers {[MnFe2O(Piv)6(hmta)2]·MeCN}n (2) and {[MnFe2O(Piv)6(hmta)2]·HPiv·n-hexane}n (3). Compounds have been characterized by elemental analysis, IR spectroscopy, X-ray crystallography, and thermogravimetry. Coordination polymers 2 crystallize in the orthorhombic space group Aba2, a = 23.127(5), b = 24.574(5), c = 19.600(5) Å and 3 in the orthorhombic space group Pbna, a = 51.214(1), b = 12.288(3), c = 19.638(4) Å. Both polymers consist of μ-oxo heterotrinuclear clusters connected by hmta molecules into one-dimensional polymeric chain (Fig. 2). The other hmta ligand coordinated to the third metal atom is terminal. Thus, the crystal structures of 2 and 3 are built up from the same parallel polymeric chains running along the c axis. The intercluster separation along the chain, which corresponds to the period of polymer, equals approximately c/2. The packing of parallel chains differs in 2 and 3 due to the template effect of solvent molecules. In 2 total potential solvent area equals 1447.2 Å3 (13%) of unit cell volume of 11139.0Å3, while in 3 this solvent area equals 2826.1 Å3 (22.9%) of unit cell volume of 12359.1 Å3. There are only van der Waals interactions between the polymeric chains in both polymeric compounds. The cavities in 2 contain aсеtonitrile solvate molecules and the channels between chains in 3 are filled by pivalate and hexane molecules. Solvate HPiv molecules form O-H…N hydrogen bonds with adjacent terminal hmta ligands in the structure of 3.
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