diff --git a/Manuscript/FarDFT.tex b/Manuscript/FarDFT.tex index d4df3dd..f0afcf2 100644 --- a/Manuscript/FarDFT.tex +++ b/Manuscript/FarDFT.tex @@ -217,11 +217,7 @@ In the KS formulation of eDFT, the universal ensemble functional (the weight-dep \begin{equation} \F{}{\bw}[\n{}{}] = \Ts{\bw}[\n{}{}] + \E{\Hxc}{\bw}[\n{}{}], \end{equation} -where -\begin{equation} - \Ts{\bw}[\n{}{}] = -\end{equation} -and +where $\Ts{\bw}[\n{}{}]$ is the noninteracting ensemble kinetic energy functional and \begin{equation} \label{eq:exc_def} \begin{split} @@ -232,7 +228,7 @@ and + \int \e{\xc}{\bw}[\n{}{}(\br{})] \n{}{}(\br{}) d\br{}. \end{split} \end{equation} -are the noninteracting ensemble kinetic energy functional and ensemble Hartree-exchange-correlation (Hxc) functional, respectively. +is the ensemble Hartree-exchange-correlation (Hxc) functional. Note that the weight-independent Hartree functional $\E{\Ha}{}[\n{}{}]$ causes the infamous ghost-interaction error (GIC) \cite{Gidopoulos_2002, Pastorczak_2014, Alam_2016, Alam_2017, Gould_2017} in eDFT, which is supposed to be cancelled by the weight-dependent xc functional $\E{\xc}{\bw}[\n{}{}]$. From the GOK-DFT ensemble energy expression in Eq.~\eqref{eq:Ew-GOK}, we obtain \cite{Gross_1988b,Deur_2019} @@ -243,10 +239,12 @@ From the GOK-DFT ensemble energy expression in Eq.~\eqref{eq:Ew-GOK}, we obtain = \Eps{I}{\bw} - \Eps{0}{\bw} + \left. \pdv{\E{\xc}{\bw}[\n{}{}]}{\ew{I}} \right|_{\n{}{} = \n{}{\bw}(\br{})}, \end{equation} where -\begin{equation} - \n{}{\bw}(\br{}) = \sum_{I=0}^{\Nens-1} \ew{I} \n{}{(I)}(\br{}) -\end{equation} -is the ensemble density, +\begin{align} + \n{}{\bw}(\br{}) & = \sum_{I=0}^{\Nens-1} \ew{I} \n{}{(I)}(\br{}), + & + \n{}{(I)}(\br{}) & = \sum_{p}^{\Norb} \ON{p}{(I)} [\MO{p}{\bw}(\br{})]^2 +\end{align} +are the ensemble and individual one-electron densities, respectively, \begin{equation} \label{eq:KS-energy} \Eps{I}{\bw} = \sum_{p}^{\Norb} \ON{p}{(I)} \eps{p}{\bw} @@ -715,13 +713,13 @@ This would be, for example, the case with the exact xc functional. Extracting excitation energies from Eqs.~\eqref{eq:bEwHF}, \eqref{eq:bEwLDA} and \eqref{eq:bEweLDA} is more tricky. To do so, we will employ Eq.~\eqref{eq:dEdw}. -The two first terms are +The two first terms are simply \begin{align} - \Eps{0}{\ew{}} & = 2(1-\ew{}) \eps{1}{\ew{}}, + \Eps{0}{\ew{}} & = 2 \eps{1}{\ew{}}, & - \Eps{1}{\ew{}} & = 2 \ew{} \eps{2}{\ew{}}, + \Eps{1}{\ew{}} & = 2 \eps{2}{\ew{}}, \end{align} -where the HF, LDA and eLDA weight-dependent orbital energies are +and the HF, LDA and eLDA weight-dependent orbital energies are \begin{subequations} \begin{align} \eps{1}{\ew{},\HF} @@ -738,14 +736,14 @@ where the HF, LDA and eLDA weight-dependent orbital energies are \eps{1}{\ew{},\LDA} & = \eHc{1} + 2(1-\ew{}) \eJ{11} + 2\ew{} \eJ{12} \\ - & + \frac{1}{2} \int \left. \fdv{\E{\xc}{\LDA}(\n{}{})}{\n{}{}} \right|_{\n{}{} = \n{}{\ew{}}(\br{})} \n{}{(0)}(\br{}) d\br{}, + & + \frac{1}{2} \int \qty{ \left. \pdv{\e{\xc}{\LDA}(\n{}{})}{\n{}{}} \right|_{\n{}{} = \n{}{\ew{}}(\br{})} + \e{\xc}{\LDA}[\n{}{\ew{}}(\br{})] } \n{}{(0)}(\br{}) d\br{}, \end{split} \\ \begin{split} \eps{2}{\ew{},\LDA} & = \eHc{2} + 2(1-\ew{}) \eJ{12} + 2 \ew{} \eJ{22} \\ - & + \frac{1}{2} \int \left. \fdv{\E{\xc}{\LDA}(\n{}{})}{\n{}{}} \right|_{\n{}{} = \n{}{\ew{}}(\br{})} \n{}{(1)}(\br{}) d\br{}, + & + \frac{1}{2} \int \qty{ \left. \pdv{\e{\xc}{\LDA}(\n{}{})}{\n{}{}} \right|_{\n{}{} = \n{}{\ew{}}(\br{})} + \e{\xc}{\LDA}[\n{}{\ew{}}(\br{})] } \n{}{(1)}(\br{}) d\br{}, \end{split} \end{align} \end{subequations} @@ -756,13 +754,13 @@ where the HF, LDA and eLDA weight-dependent orbital energies are \eps{1}{\ew{},\eLDA} & = \eHc{1} + (1-\ew{})(2\eJ{11} - \eK{11}) + \ew{}(2\eJ{12} - \eK{12}) \\ - & + \frac{1}{2} \int \left. \fdv{\bE{\xc}{\ew{}}(\n{}{})}{\n{}{}} \right|_{\n{}{} = \n{}{\ew{}}(\br{})} \n{}{(0)}(\br{}) d\br{}, + & + \frac{1}{2} \int \qty{ \left. \pdv{\be{\xc}{\ew{}}(\n{}{})}{\n{}{}} \right|_{\n{}{} = \n{}{\ew{}}(\br{})} + \be{\xc}{\ew{}}[\n{}{\ew{}}(\br{})] } \n{}{(0)}(\br{}) d\br{}, \end{split} \\ \begin{split} \eps{2}{\ew{},\eLDA} & = \eHc{2} + (1-\ew{})(2\eJ{12} - \eK{12}) + \ew{}(2\eJ{22} - \eK{22}) \\ - & + \frac{1}{2} \int \left. \fdv{\bE{\xc}{\ew{}}(\n{}{})}{\n{}{}} \right|_{\n{}{} = \n{}{\ew{}}(\br{})} \n{}{(1)}(\br{}) d\br{}, + & + \frac{1}{2} \int \qty{ \left. \pdv{\be{\xc}{\ew{}}(\n{}{})}{\n{}{}} \right|_{\n{}{} = \n{}{\ew{}}(\br{})} + \be{\xc}{\ew{}}[\n{}{\ew{}}(\br{})] } \n{}{(1)}(\br{}) d\br{}, \end{split} \end{align} \end{subequations}