Benchmark Study of the Exchange-Corrected Density Functionals: Application to Strained Boron Nitride Clusters

Abstract

We present a quantum chemical study of three small boron nitride clusters B2N2, B3N3 and B4N4. Their structure and electronic characteristics are calculated by means of the coupled cluster (CC) and density functional theory (DFT) techniques. In order to find the best match with the coupled cluster data the twenty-four DFT exchange-corrected functionals are analyzed. According to our results, B3P86V5 and B97 functionals reproduce well the geometry of small boron-nitrides, whereas for the electronic characteristics OP and VWN functionals give the closest to CC results. Note that prevalent B3LYP and PBE0 DFT-functionals demonstrate lower accuracy.