“…This Table illustrates the improvement of tuned over standard LC-DFT when comparing with static β tot values calculated by the MP2 method, which has been shown to produce reasonably accurate molecular hyperpolarizabilities. 22,40,67,[76][77][78] The qualitative observations that can be drawn from Table 5 are similar to those obtained when using experimental data as reference; LC-DFT tends to underestimate hyperpolarizabilities, the tuning procedure roughly halves this error, and the improvement is more noticeable in polar environments. We also note that, although MP2 tends to somehow overshoot β ijk values compared to coupled cluster calculations, this effect is usually small when using large enough basis sets, similar to the ones used here (see, e.g., Refs.…”