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Manuscript/ufGW.tex

@@ -396,7 +396,7 @@ The regularized solutions $\reps{p,s}{\GW}$ are then obtained by solving the fol
 	\eps{p}{\HF} + \rSigC{p}(\omega;\eta) - \omega = 0
 \end{equation}
 
-The most common and well-established way of regularizing $\Sigma$ is via the simple regularizer $f_\eta(\Delta) = (\Delta \pm \eta)^{-1}$, a strategy somehow related to the imaginary shift used in multiconfigurational perturbation theory. \cite{Forsberg_1997}
+The most common and well-established way of regularizing $\Sigma$ is via the simple regularizer $f_\eta(\Delta) = (\Delta \pm \ii \eta)^{-1}$, a strategy somehow related to the imaginary shift used in multiconfigurational perturbation theory. \cite{Forsberg_1997}
 Other choices are legitimate like the regularizers considered by Head-Gordon and coworkers within orbital-optimized second-order M{\o}ller-Plesset theory. \cite{Lee_2018a,Shee_2021}
 
 Our investigations have shown that the following regularizer