Density functional benchmark studies on structure and energetics of 3d transition metal mononitrides

Abstract

Abstract: We report the results of a benchmarking study on generalized gradient approximation (GGA), meta-GGA, hybrid GGA, and hybrid meta-GGA density functional theory (DFT) methods for 3d transition metal mononitrides (3 d-TMNs). The selected DFT functionals are, B97-D, BLYP, BP91, MPW91, PBE96, PW91, M06-L, B3LYP, B97, BHandH, PBE0, M05, M05-2X, M06, M06-2X, M06-HF and TPSSh. The performances of these DFT functionals are assessed by calculating the bond distance, harmonic vibrational frequency and atomization energy of 3 d-TMNs. The results are compared with the available experimental and high-level ab initio results. The calculated results show that MPW91, M06-L, and B3LYP functionals provide better results than the other functionals that are taken in this study. In general, the functionals with significant Hartree–Fock exchange show poor performance in most of the 3 d-TMNs. Hence, these functionals are not recommended for the studies of structure and energetics in 3 d-TMNs. Graphical Abstract: SYNOPSIS The performance of seventeen DFT functionals for the structure and energetics of eight 3 d-TMNs are assessed. It is noted that the MPW91, M06-L, and B3LYP functionals show good performance for both structure and energetic properties of 3 d-TMNs. The functionals with significant Hartree–Fock exchange show poor performance in 3 d-TMNs. [Figure not available: see fulltext.].