Hydrothermal Synthesis and Characterization of Chabazite-Type Cobaltoaluminophosphate with an Encapsulated Cobalt Complex: Co3Al3 (PO4)6Co(DETA)2 · (H2O)3

A chabazite-type cobaltoaminophosphate containing mixed- valence Co atoms with the encapsulated cobalt complex Co3Al3 (PO4)6Co(DETA)2 · 3(H2O) (DETA, diethyltriamine) has been hydrothermally synthesized and structurally determined. The compound with a chabazite structure crystallizes in the rhombohedral space group R with a=13.792(2) ?, c=14.997(4) ?, V=2470.6(9) ?3, and Z=2. The negative open framework contains CoIIO4 units and is disordered with AlO4 units in the same position. The charge-balancing cations, [Co(DETA)2] 3+, are located in the big cages. The compound was characterized by infrared spectroscopy, diffuse reflectance spectrocopy, X-ray photoelectron spectroscoy, and differential thermal analyses thermogravimetry. The results show that the compound can exist up to 300°C in N2.