CPL calculations of [7]helicenes with alleged exceptional emission dissymmetry values

Any device based on materials exhibiting circularly polarized luminescence (CPL) requires a high degree of circular polarization, quantified through the dissymmetry factor glum and related quantities such as the CPL brightness. However, maximizing |glum| is not an easy task. For a given chiral scaffold, for example, helicenes, glum is usually confined below a certain threshold (e.g. 10−3–10−2). Computational tools able to predict dissymmetry values in an accurate way are therefore of utmost importance. Intrigued by exceptionally high |glum| values reported for two 1,1′-bitriphenylene-based [7]helicenes, we tested time-dependent density functional theory (TD-DFT) including solvation effects in predicting these large gabs and glum values, in comparison with a reference [7]helicene. The quality of our results is discussed in comparison with a literature dataset.