Benchmarking DFT methods on linear and nonlinear electric properties of spatially confined molecules

Abstract

AbstractThe accurate evaluation of molecular electric properties still constitutes a challenge for density functional theory (DFT) methods. Moreover, some new issues appear, within this area of research, that require analysis. One of them concerns the electric properties of confined matter. This study aims at a quantitative evaluation of the performance of DFT framework in the description of dipole moment, polarizability, and first hyperpolarizability of the isolated and spatially confined molecules. The calculations were performed using a set of 35 exchange‐correlation functionals. The reference data were determined employing the highly accurate CCSD(T) method. To mimic the effect of spatial confinement the cylindrically symmetric harmonic oscillator potential was applied. Based on the conducted research it was found that the behavior of the considered functionals substantially differs depending on the studied electric property and molecule. Moreover, it was observed that the strength of spatial confinement strongly influences the performance of DFT methods.