Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 40
- Best energy (Ha)
- -1.83715
H2
H2 VQE accuracy-cost benchmark · hardware · ibm_brussels
Final energy-1.8371506553hartree
Shots4096
Runtime executionsession
Resilience0
MappingPT
Active space2e,2o
Parity mapping with full symmetry tapering · Shots and precision · Resilience settings
Execution
- Mode
- hardware
- Provider
- IBM Quantum
- Compute resource
- ibm_brussels
- Resource type
- ibm quantum hardware
- Processor family
- Eagle r3
- Processor model
- Not recorded
- Processor revision
- Not recorded
- Qubits
- Not recorded
- Connectivity
- Not recorded
- Runtime execution
- session
- Shots
- 4096
- Precision
- 0.015625
- Resilience
- 0
- Submitted
- 2026-04-01T00:16:59+02:00
- Wall time (s)
- 141
Molecular system
- Charge
- 0
- Multiplicity
- 1
- Basis
- STO-3G
- Active space
- 2e,2o
- Active electrons
- 2
- Spatial orbitals
- 2
- Active orbital indices
- Not recorded
- Geometry units
- angstrom
Circuit
- Logical qubits
- 1
- Physical qubits
- Not recorded
- Parameters
- Not recorded
- Depth
- 1
- Two-qubit gates
- 0
- Hamiltonian terms
- Not recorded
Scientific provenance
- Cohort
- published h2
- Reference method
- exact diagonalization
- Reference energy (Ha)
- -1.85728
- Energy convention
- Published H2 benchmark electronic-energy convention
- Absolute error (Ha)
- 0.0201244
- Signed error (Ha)
- 0.0201244
- Total QPU time (s)
- 63
- Calibration time
- Not recorded
- Mean readout error
- Not recorded
- Mean two-qubit gate error
- Not recorded
Software
- Qiskit
- 1.4.3
- Qiskit Aer
- 0.17.1
- Qiskit Algorithms
- 0.3.1
- Qiskit Ibm Runtime
- 0.40.1
- Qiskit Nature
- 0.7.2
- Qiskit Nature Pyscf
- 0.4.0
Molecular geometry (angstrom)
| Atom | x | y | z |
|---|---|---|---|
| H | 0 | 0 | 0 |
| H | 0 | 0 | 0.735 |
Dataset publication
Associated articles
- Accuracy-Cost Trade-offs for Reference VQE Calculations of H2 on IBM Quantum Hardware submitted to Quantum Science and Technology
- Accuracy-Cost Trade-offs for Reference VQE Calculations of H2 on IBM Quantum Hardware DOI 10.48550/arXiv.2604.11478 arXiv 2604.11478 published preprint
Compute access
- Fraunhofer Quantum Now and EQeS · IBM Quantum · allocation: Fraunhofer Quantum Now
Optimization trajectory
21 recorded objective evaluations. Charts use cumulative time so convergence cost remains comparable across calculations.
Download trajectory CSV · Download trajectory JSON
| Attempt | Outcome | Energy (Ha) | Elapsed (s) | Quantum (s) | Parameters |
|---|---|---|---|---|---|
| 1 | succeeded | -1.8229780036 | 8.48842 | 3 | — |
| 2 | succeeded | -0.5770825866 | 6.76554 | 3 | — |
| 3 | succeeded | -0.8830966637 | 6.52018 | 3 | — |
| 4 | succeeded | -1.3229182509 | 7.48256 | 3 | — |
| 5 | succeeded | -1.8025990176 | 6.52684 | 3 | — |
| 6 | succeeded | -1.7955757857 | 6.3914 | 3 | — |
| 7 | succeeded | -1.8327903067 | 6.2905 | 3 | — |
| 8 | succeeded | -1.8111793396 | 6.3654 | 3 | — |
| 9 | succeeded | -1.8371506553 | 7.03764 | 3 | — |
| 10 | succeeded | -1.8153824789 | 6.34066 | 3 | — |
| 11 | succeeded | -1.8273475838 | 6.88694 | 3 | — |
| 12 | succeeded | -1.8329285096 | 6.33007 | 3 | — |
| 13 | succeeded | -1.8245736496 | 6.92418 | 3 | — |
| 14 | succeeded | -1.8237590264 | 6.83286 | 3 | — |
| 15 | succeeded | -1.8308271945 | 6.70419 | 3 | — |
| 16 | succeeded | -1.8306841042 | 6.20138 | 3 | — |
| 17 | succeeded | -1.8301193459 | 6.52285 | 3 | — |
| 18 | succeeded | -1.8334585815 | 6.45719 | 3 | — |
| 19 | succeeded | -1.8340591124 | 7.16426 | 3 | — |
| 20 | succeeded | -1.8267437947 | 6.5497 | 3 | — |
| 21 | succeeded | -1.8290060863 | 6.70075 | 3 | — |