IR and thermal studies on barium oxomolybdenum(VI) oxalate

Abstract

The complex Ba[Mo 2O 5(C 2O 4) 2(H 2O) 2]·2H 2O (BMO) was prepared and characterized by chemical analysis and IR spectral studies. TG and DTA techniques were used to study the thermal decomposition. The dehydration of BMO takes place in two steps between 115 and 230°C, two moles of water being lost in each step. The decomposition of anhydrous BMO occurs between 230 and 360°C in three steps. The first two steps occur in the temperature ranges 230–255 and 255–295°C to give intermediates having the tentative compositions Ba[Mo 2O 5(C 2O 4)(CO 3)] and BaMo 2O 7·CO 2, respectively, the latter then decomposing between 295 and 360°C to give the end product. The end product consists of BaMoO 4, BaMo 2O 7 and some other phase which could not be identified.