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clean up corrections

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Pierre-Francois Loos 2020-02-10 17:07:38 +01:00
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BSE-PES.tex
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@ -186,7 +186,7 @@ The combination of the many-body Green's function $GW$ approximation and the Bet
The BSE formalism can also be employed to compute ground-state correlation energies thanks to the adiabatic-connection fluctuation-dissipation theorem (ACFDT).
Here, we study the topology of the ground-state potential energy surfaces (PES) of several diatomic molecules near their equilibrium bond length.
Thanks to comparisons with state-of-art computational approaches, we show that ACFDT@BSE is surprisingly accurate, and can even compete with coupled cluster methods in terms of total energies and equilibrium bond distances for the considered systems.
However, we sometimes observe unphysical irregularities on the ground-state PES in relation with discontinuities of some $GW$ quasiparticle energies, questioning their identification as quasiparticle solution (\textit{i.e.}, the solution of the quasiparticle equation with the largest spectral weight).
However, we sometimes observe unphysical irregularities on the ground-state PES in relation with discontinuities of some $GW$ quasiparticle energies, questioning their identification as quasiparticle solution (\textit{i.e.}, as solution of the quasiparticle equation with the largest spectral weight).
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@ -602,7 +602,7 @@ Similarly to what is observed for \ce{LiF} and \ce{BF}, there are irregularities
However, BSE@{\GOWO}@HF is the closest to the CC3 curve, with an error on the correlation energy of $1\%$ and an estimated bond length of $2.640$ bohr (via a Morse fit) at the BSE@{\GOWO}@HF/cc-pVQZ level.
Note that, for this system, triplet (and then singlet) instabilities appear for quite short bond lengths.
However, around the equilibrium structure, we have not encountered any instabilities.
This is an important outcome of the present study as the difficulties encountered at large interatomic distance (\ie, close to the dissociation limit) do not prevent the BSE approach to be potentially useful and accurate in the vicinity of equilibrium distances.
This is an important outcome of the present study as the difficulties encountered at large interatomic distances (\ie, close to the dissociation limit) do not prevent the BSE approach to be potentially useful and accurate in the vicinity of equilibrium distances.
Furthermore, preliminary calculations could not detect any singlet instabilities in the vicinity of the lowest singlet excited-state minima.
\xavier{ Although we considered here only a limited set of compounds,