Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 40
- Best energy (Ha)
- -1.84215
H2
H2 VQE accuracy-cost benchmark · hardware · ibm_brussels
Final energy-1.8421456952hartree
Shots8192
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
- 8192
- Precision
- 0.0110485
- Resilience
- 0
- Submitted
- 2026-04-01T00:19:33+02:00
- Wall time (s)
- 189
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)
- 0.0151293
- Signed error (Ha)
- 0.0151293
- Total QPU time (s)
- 105
- 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 | -1.8153998221 | 10.2309 | 5 | — |
| 2 | succeeded | -0.5666963275 | 8.8679 | 5 | — |
| 3 | succeeded | -0.8696814637 | 9.34471 | 5 | — |
| 4 | succeeded | -1.3067283022 | 8.58232 | 5 | — |
| 5 | succeeded | -1.7913119621 | 8.99056 | 5 | — |
| 6 | succeeded | -1.7654803933 | 8.9182 | 5 | — |
| 7 | succeeded | -1.8389918218 | 9.25942 | 5 | — |
| 8 | succeeded | -1.8253809759 | 8.96858 | 5 | — |
| 9 | succeeded | -1.8316559027 | 8.49279 | 5 | — |
| 10 | succeeded | -1.8356821309 | 8.58898 | 5 | — |
| 11 | succeeded | -1.8326312309 | 9.26361 | 5 | — |
| 12 | succeeded | -1.8421456952 | 8.91632 | 5 | — |
| 13 | succeeded | -1.8339591258 | 8.66754 | 5 | — |
| 14 | succeeded | -1.8356891734 | 8.86656 | 5 | — |
| 15 | succeeded | -1.8353978510 | 8.98882 | 5 | — |
| 16 | succeeded | -1.8416776822 | 8.91233 | 5 | — |
| 17 | succeeded | -1.8357775187 | 9.072 | 5 | — |
| 18 | succeeded | -1.8359897103 | 9.33228 | 5 | — |
| 19 | succeeded | -1.8345588421 | 8.81796 | 5 | — |
| 20 | succeeded | -1.8369612373 | 9.23672 | 5 | — |
| 21 | succeeded | -1.8275803770 | 8.6992 | 5 | — |