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All instances / Hydrogen chain

Hydrogen chain H12 chain, open, R = 1.51178, STO-3G

Best values (rules §6)

best variational -0.5268575 VQE
10.1021/acs.jctc.3c00319 · the lowest unflagged variational energy, a strict variational bound

Energies as E/N (Ha). Classes are different claims and are not ranked against each other.

The Hamiltonian

H = −½ ∑i ∇i2 − ∑i,I 1/|ri − RI| + ∑i<j 1/|ri − rj| + ∑I<J 1/|RI − RJ|

Hydrogen chain: 12 protons equally spaced on a line, spacing R = 1.51178 bohr, open (a finite molecule); N↑ = 6, N↓ = 6. Projected onto the STO-3G basis set; full CI in it is this instance's exact energy. Hartree atomic units, nuclear repulsion included; the energy per atom is E/N.

geometry
chain
atoms
12
boundary
open
N_up
6
N_dn
6
R
1.51178
basis
STO-3G
energies
1

Stored as a total energy in Hartree, nuclear repulsion included (rules §13); quoted here as E/N (Ha), the energy per atom (how the conversion works).

Every published energy

Grouped by what the number is. The exact energy comes first where there is one; in every other group the lowest unflagged energy is its best value, and each row's distance is to that best (rules §6).

Strict variational upper bounds (1)

Energies that a variational state reached (VMC, DMRG and MPS at finite bond dimension, PEPS, NQS, VQE). Each is an upper bound on the ground-state energy.

E/N (Ha)distance to class bestσVar(E)V-score methodsourcecodeyearcomment
-0.5268575best variational 0 n/a n/a n/a VQE
peer reviewed
10.1021/acs.jctc.3c00319 tencent-quantum-lab/TenCirChem 2023

How these numbers were read

Where each number below was read, and how it was checked.

-0.5268575, VQE

Checked 2026-10-20 · source text of arXiv:2303.10825 read locally (pypdf layout text; the generator finds every value again on its line), no LLM transcription of numbers; single reading (Sonnet reader)

Reported as. -6,322.29 mHa per total; R = 0.8 Å = 1.51178 bohr

Table 1; sources/2303.10825.txt line 660; version read: arXiv text; journal copy not reached (publisher returned HTTP 403 or a login page, 2026-10-21); read again when reachable (RULES.md §8) | Table 1 header line 650 'Energy Error (mH) (mH)'; line 636-637 'STO-3G ... interatomic distance set to 0.8 Å'; thousands separator comma: -2,167.55 mH = -2.16755 Ha | Unit mH printed in header only; inferred from magnitude and header. Boundary not stated, open assumed. Nuclear repulsion not stated. Table also prints error vs FCI in mH (would imply FCI = energy - error, not printed itself). | reader confidence medium

Coverage

Newest published number here: 2023.

This instance as data

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