Quantitative comparison of TDDFT-calculated high harmonic generation yields in ring-shaped organic molecules

We calculate high harmonic generation (HHG) yields in benzene, cyclohexene, and cyclohexane using time-dependent density functional theory (TDDFT). Our goal is to obtain quantitative agreement with experimental yield ratios. We simulate gas-phase experimental conditions by averaging over the molecular orientation angles. By resolving the yield into contributions from individual molecular orbitals, we show that quantitative agreement between theory and experiment is suppressed due to a difference between DFT-computed and experimental ionization potentials. We further show that by reweighting individual orbital contributions through an adjustment in the tunnel-ionization step of HHG, one can account for this difference to obtain more realistic yields in good quantitative agreement with experimental results [1].

[1] A. F. Alharbi, A. E. Boguslavskiy, N. Thiré, B. E. Schmidt, F. Légaré, T. Brabec, M. Spanner, and V. R. Bhardwaj, Phys. Rev. A 92, 041801 (2015).