Conclusions
By computationally modelling the reaction of a diiron-mediated N–N bond cleavage (the decomposition reaction of complex Cp*Fe(μ -SEt)2(μ -NHNH3)FeCp*(Cp*=η 5-C5Me5,1 ) to Cp*Fe(μ -SEt)2(μ -NH)FeCp*(2 ) and NH3), a wide range of DFT functionals have been performed for the benchmark study compared with the higher level MP2 and DLPNO-CCSD(T) results. The DFT benchmarks show that the HGGA functional of B1B95 is the best functional among all of the benchmarked DFT functionals for the structures and relative energies. The reliability of these three functionals (mPW1PBE, HSE1PBE and HSEh1PBE) follows the B1B95. This work can help better choosing reasonable DFT functional to study the N–N bond cleavage of dinuclear clusters.