DFT investigation of the influence of Jahn–Teller distortion on the aromaticity in square-planar arsenic and antimony clusters

Density functional theory (DFT) calculations were performed to investigate aromaticity of tetra atomic metalloid clusters, As42− and Sb42−. The careful analysis of nuclear independent chemical shifts (NICS) revealed strong σ antiaromatic and week π aromatic character of investigated species. This unexpected behavior is explained through the analysis of antagonistic paratropic and diatropic contributions, and with detailed adaptive natural density partitioning (AdNDP) analysis. Furthermore, we investigated aromatic/antiaromatic behavior of Jahn–Teller (JT) active species As4− and Sb4−. NICS parameters have been scanned along the Intrinsic Distortion Path (IDP) showing strong antiaromaticity which decreases with increasing deviation from D4h to D2h symmetry.

Graphical abstractWe report detailed analysis and explanation of antiaromaticity in As42− and Sb42− rectangular metalloid clusters. In addition, the influence of Jahn–Teller distortion on aromatic behavior in As4− and Sb4− was explored. NICS values were scanned along the Intrinsic Distortion Path (IDP).Figure optionsDownload full-size imageDownload as PowerPoint slide