ON THE CRYSTALLIZATION AND NATURE OF THE MICROPOROUS BORON-ALUMINUM OXO CHLORIDE BAC(10)

A novel microporous boron-aluminium oxo chloride [BAC(10)] has been sy nthesized hydrothermally. The crystallisation of the material was stud ied by X-ray diffraction (XRD), inductively coupled plasma analysis (I CP), IR spectroscopy and magic-angle spinning nuclear magnetic resonan ce (MAS NMR) spectroscopy. Its basic building units are triangular BO3 , tetrahedral BO4 and octahedral AlO6. As BAC(10) crystallises, some o f the BO3 groups are transformed into BO4 species in the solid. Adsorp tion measurements reveal that BAC(10) has a microporous structure, whe reas the fact that the Cl- ions in BAC(10) can be partially exchanged by Br- ions suggests that this compound possesses a cationic framework . Thermal decomposition studies indicate that BAC(10) is stable up to 300 degrees C, and at temperatures above 325 degrees C the crystal str ucture of BAC(10) collapses with the evolution of HCl and H2O from the sample.