Ab initio and density functional theory study of the diazene isomerization

The HF, MP2, QCISD(T), G1, G2, and G2MP2 ab initio and twenty-two density functional theory (DFT) methods were used to perform the computational studies of the syn- and cis-diazene ransformation into trans-diazene. In all calculations the Gaussian type 6–311 + G(2d,2p) basis set was used. The DFT computed geometries and energies are compared with ab initio results and the validity of several DFT methods for studying this and similar molecular systems are evaluated.