From 5c4f0bfbb67a53a91e358bee3cbd59a8da75a8bc Mon Sep 17 00:00:00 2001 From: Pierre-Francois Loos Date: Sat, 5 Dec 2020 13:37:52 +0100 Subject: [PATCH] OK with abstract and intro --- Manuscript/EPAWTFT.tex | 20 -------------------- 1 file changed, 20 deletions(-) diff --git a/Manuscript/EPAWTFT.tex b/Manuscript/EPAWTFT.tex index 4440395..ef4e9c3 100644 --- a/Manuscript/EPAWTFT.tex +++ b/Manuscript/EPAWTFT.tex @@ -175,30 +175,10 @@ has emerged as an instrument of choice among the vast array of methods developed However, the properties of perturbation theory in the complex plane are essential for understanding the quality of perturbative approximations on the real axis. -% Good old Schroedinger -%The electronic Schr\"odinger equation, -%\begin{equation} -% \hH \Psi = E \Psi, -%\end{equation} -%is the starting point for a fundamental understanding of the behaviour of electrons and, thence, of chemical structure, bonding and reactivity. -%However, as famously stated by Dirac: \cite{Dirac_1929} -%\begin{quote} -% \textit{``The underlying physical laws necessary for the mathematical theory of a large part of physics and the whole of chemistry are thus completely known, and the difficulty is only that the exact application of these laws leads to equations much too complicated to be soluble. -% It therefore becomes desirable that approximate practical methods of applying quantum mechanics should be developed, which can lead to an explanation of the main features of complex atomic systems without too much computation.''} -%\end{quote} -%Indeed, as anticipated by Dirac, accurately predicting the energetics of electronic states from first principles has been one of the grand challenges faced by theoretical chemists and physicists since the dawn of quantum mechanics. - -% RSPT -%Together with the variational principle, perturbation theory is one of the very few essential tool for describing realistic quantum systems for which it is impossible to find the exact solution of the Schr\"odinger equation. -%In particular, time-independent Rayleigh--Schr\"odinger perturbation theory \cite{RayleighBook,Schrodinger_1926} has cemented itself as an instrument of choice in the armada of theoretical and computational methods that have been developed for this purpose. \cite{SzaboBook,JensenBook,CramerBook,HelgakerBook,ParrBook,FetterBook,ReiningBook} - % Moller-Plesset -%\hugh{Accurately predicting the electronic energy is the primary focus of electronic structure theory, in -%principle providing a fundamental understanding of chemical structure, bonding, and reactivity. In electronic structure theory, the workhorse of time-independent perturbation theory is M\o{}ller--Plesset (MP) %perturbation theory,\cite{Moller_1934} which remains one of the most popular methods for computing the electron correlation energy.\cite{Wigner_1934,Lowdin_1958} -%\trashHB{an old yet important concept, first introduced by Wigner \cite{Wigner_1934} and later defined by L\"owdin. \cite{Lowdin_1958}} This approach estimates the exact electronic energy by constructing a perturbative correction on top of a mean-field Hartree--Fock (HF) approximation.\cite{SzaboBook} The popularity of MP theory stems from its black-box nature, size-extensivity, and relatively low computational scaling,