Theoretical Study of Thermite Reaction Enthalpy for Metal Composite Oxides of Ferrite Series

By using the density functional theory（DFT）,the thermite reaction enthalpies of 7kinds of common metal oxides were calculated with GGA-PBE,GGA-BLYP,GGA-PW91 functional in conjuction with DNP basis set in the Material Studio package.The calculated values were compared with the experimental ones to determine the optimum calculation basis set level.On this basis,the thermite reaction enthalpies of six kinds of metal composite oxides of ferrite series（CuFe 2 O 4 ,NiFe 2 O 4 ,CoFe 2 O 4 ,MgFe 2 O 4 ,ZnFe 2 O 4 and MnFe 2 O 4 ）were theoretically calculated,and Hess′s law was employed to calculate their standard molar enthalpies of formation.The results show that the claclulation method based on the GGA-PBE functional in conjuction with DNP basis set is most precise,and the mean error（ME）of common thermite reactions between calculated and experimental enthalpies is 7.072kJ/mol.At GGA-PBE/DNP level,thermite reaction enthalpies of the six compounds are-3 695.02,-3 388.53,-3 380.13,-841.06,-3 142.57and-2 738.40kJ/mol,respectively,which is little different with that of the equivalent physical mixed metal oxides.The standard molar enthalpies of formation of six substances are-992.62,-1 092.12,-1 090.13,-1 431.13,-1 185.15and-1 311.78kJ/mol,respectively.