diff --git a/dynker.tex b/dynker.tex index 4ea48e2..fff9bec 100644 --- a/dynker.tex +++ b/dynker.tex @@ -639,17 +639,17 @@ In the case of BSE2, the perturbative partitioning is simply } \begin{ruledtabular} \begin{tabular}{|c|ccccccc|c|} - Singlets & BSE2 & pBSE2 & pBSE2(dTDA) & dBSE2 & BSE2(TDA) & pBSE2(TDA) & dBSE2(TDA) & Exact \\ + Singlets & BSE2 & pBSE2 & pBSE2(dTDA) & dBSE2 & BSE2(TDA) & pBSE2(TDA) & dBSE2(TDA) & Exact \\ \hline - $\omega_1$ & 1.84903 & 1.90940 & 1.90950 & 1.90362 & 1.86299 & 1.92356 & 1.92359 & 1.92145 \\ - $\omega_2$ & & & & & & & & \\ - $\omega_3$ & & & & 4.47124 & & & 4.47097 & 3.47880 \\ + $\omega_1^{\updw}$ & 1.84903 & 1.90940 & 1.90950 & 1.90362 & 1.86299 & 1.92356 & 1.92359 & 1.92145 \\ + $\omega_2^{\updw}$ & & & & & & & & \\ + $\omega_3^{\updw}$ & & & & 4.47124 & & & 4.47097 & 3.47880 \\ \hline - Triplets & BSE2 & pBSE2 & pBSE2(dTDA) & dBSE2 & BSE2(TDA) & pBSE2(TDA) & dBSE2(TDA) & Exact \\ + Triplets & BSE2 & pBSE2 & pBSE2(dTDA) & dBSE2 & BSE2(TDA) & pBSE2(TDA) & dBSE2(TDA) & Exact \\ \hline - $\omega_1$ & 1.38912 & 1.44285 & 1.44304 & 1.42564 & 1.40765 & 1.46154 & 1.46155 & 1.47085 \\ - $\omega_2$ & & & & & & & & \\ - $\omega_3$ & & & & 4.47797 & & & 4.47767 & \\ + $\omega_1^{\upup}$ & 1.38912 & 1.44285 & 1.44304 & 1.42564 & 1.40765 & 1.46154 & 1.46155 & 1.47085 \\ + $\omega_2^{\upup}$ & & & & & & & & \\ + $\omega_3^{\upup}$ & & & & 4.47797 & & & 4.47767 & \\ \end{tabular} \end{ruledtabular} \end{table*} @@ -720,9 +720,13 @@ For the double excitation, dBSE2 yields a slightly better energy, yet still in q %\end{gather} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -\section{Take-home messages} +\section{Take-home message} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% -What have we learned here? +The take-home message of the present paper is that dynamical kernels have much more to give that one would think. +In more scientific terms, dynamical kernels can provide, thanks to their frequency-dependent nature, additional excitations that can be associated to higher-order excitations (such as the infamous double excitations). +However, they sometimes give too much, and generate spurious excitations, \ie, excitation which does not corresponds to any physical excited state. +The appearance of these factitious excitations is due to the approximate nature of the dynamical kernel. +Moreover, because of the non-linear character of the linear response problem when one employs a dynamical kernel, it is computationally more involved to access these extra excitations. %%%%%%%%%%%%%%%%%%%%%%%% \acknowledgements{