Thermal decomposition of inclusion compounds on the base of the metal–organic framework [Zn4(dmf)(ur)2(ndc)4

Abstract

Inclusion compounds based on metal–organic frameworks (MOFs) have promising practical applications in gas storage, the separation, and fine purification of substances, and also in catalysis. These MOFs are crystalline compounds consisting of metal ions coordinated by bridging organic ligands with the formation of porous structures. We study the kinetic stability of two inclusion compounds on the base of the new framework: [Zn4(dmf)(ur)2(ndc)4]·6C6H6 and [Zn4(dmf)(ur)2(ndc)4]·5C6H5CH3 (ndc2− = 2,6-naphtalenedicarboxylate, ur = hexamethylentetramin, dmf = N,N′-dimethylformamide). The inclusion compound with benzene is more stable than the compound with toluene. The reduced stability of the toluene compound may be connected with the toluene molecule’s shape: the C6H5CH3 molecule is more bulky and asymmetric than the C6H6 molecule; the MOF matrix structure must be greatly distorted to include the toluene molecules and the compound stability decreases.