Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 30
- Best energy (Ha)
- -1.84885
H2
H2 VQE accuracy-cost benchmark · hardware · ibm_brussels
Final energy-1.8222864462hartree
Shots256
Runtime executionsingle-job
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
- single-job
- Shots
- 256
- Precision
- 0.0625
- Resilience
- 0
- Submitted
- 2026-02-12T21:12:39+01:00
- Wall time (s)
- 97
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)
- 0.0349886
- Signed error (Ha)
- 0.0349886
- Total QPU time (s)
- 25
- 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
18 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 | -1.8296228744 | 5.35901 | 1 | — |
| 2 | succeeded | -0.5393873422 | 5.37901 | 1 | — |
| 3 | succeeded | -0.9526742481 | 5.03649 | 1 | — |
| 4 | succeeded | -1.6236299802 | 4.55486 | 1 | — |
| 5 | succeeded | -1.6916784741 | 4.82639 | 1 | — |
| 6 | succeeded | -1.8488485521 | 5.04949 | 1 | — |
| 7 | succeeded | -1.7637943150 | 4.51762 | 1 | — |
| 8 | succeeded | -1.7739577931 | 6.41475 | 2 | — |
| 9 | succeeded | -1.8259546603 | 8.02574 | 4 | — |
| 10 | succeeded | -1.8186095435 | 8.46838 | 4 | — |
| 11 | succeeded | -1.8318949408 | 4.61866 | 1 | — |
| 12 | succeeded | -1.8446079771 | 5.05097 | 1 | — |
| 13 | succeeded | -1.8273681853 | 4.729 | 1 | — |
| 14 | succeeded | -1.8242636435 | 5.13883 | 1 | — |
| 15 | succeeded | -1.8090010490 | 4.73837 | 1 | — |
| 16 | succeeded | -1.8251134962 | 4.58864 | 1 | — |
| 17 | succeeded | -1.8208729212 | 4.74893 | 1 | — |
| 18 | succeeded | -1.8222864462 | 5.9115 | 1 | — |