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Pierre-Francois Loos 2022-03-06 15:13:41 +01:00
parent 21d4fed58a
commit 832d8ce904
3 changed files with 4 additions and 8 deletions
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Manuscript/seniority.tex
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@ -64,13 +64,13 @@
% Abstract
\begin{abstract}
%aimed at recovering both static and dynamic correlation,
%Aiming at recovering both static and dynamic correlation,
We propose a novel partitioning of the Hilbert space, hierarchy configuration interaction (hCI),
where the degree of excitation (with respect to a given reference) and the seniority number (number of unpaired electrons) are combined in a single hierarchy parameter.
The key appealing feature of hCI is that each level of the hierarchy accounts for all classes of determinants that share the same scaling with the system size.
where the excitation degree (with respect to a given reference determinant) and the seniority number (\ie, the number of unpaired electrons) are combined in a single hierarchy parameter \titou{in order to recover both static and dynamic correlations at a similar rate?}
The key appealing feature of hCI is that each hierarchy level accounts for all classes of determinants that share the same scaling with system size.
%number of electrons and basis functions.
%In this way, it accounts for low-seniority high-excitation determinants lacking in excitation-based CI, while keeping the same computational scaling with system size.
By surveying the dissociation of multiple molecular systems, we found that the overall performance of hCI usually exceeds or at least parallels that of excitation-based CI.
By surveying the dissociation of multiple molecular systems, we found that the overall performance of hCI usually exceeds or, at least, parallels that of excitation-based CI.
%By surveying the dissociation of multiple molecular systems, we examined how fast hCI and their excitation-based and seniority-based parents converge as we step up towards the exact full CI limit.
%The overall performance of hCI usually exceeds or at least parallels that of excitation-based CI.
%For small systems and basis sets, doubly-occupied CI (the first level of seniority-based CI) often remains the best option, but becomes impractical for larger systems or basis sets, and for higher accuracy.

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excitation_energies/C2_aug-cc-pvdz/GS_HF/plot_state_2.gnu
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@ -6,8 +6,6 @@ filename2 = 'map_seniority_vs_excitation_state_2.dat'
set zrange[0.0:5.0]
set terminal wxt enhanced size 400,600
unset key
set ticslevel 0

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excitation_energies/C2_aug-cc-pvdz/GS_HF/plot_state_3.gnu
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@ -6,8 +6,6 @@ filename2 = 'map_seniority_vs_excitation_state_3.dat'
set zrange[0.0:6.0]
set terminal wxt enhanced size 400,600
unset key
set ticslevel 0