Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 40
- Best energy (Ha)
- -1.84009
H2
H2 VQE accuracy-cost benchmark · hardware · ibm_brussels
Final energy-1.8400882812hartree
Shots4096
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
- 4096
- Precision
- 0.015625
- Resilience
- 0
- Submitted
- 2026-03-06T23:50:03+01:00
- Wall time (s)
- 143
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)
- 0.0171867
- Signed error (Ha)
- 0.0171867
- Total QPU time (s)
- 67
- 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 | -1.8074856027 | 11.0992 | 7 | — |
| 2 | succeeded | -0.5697342115 | 6.86925 | 3 | — |
| 3 | succeeded | -0.8675343468 | 6.5332 | 3 | — |
| 4 | succeeded | -1.3171237759 | 6.35932 | 3 | — |
| 5 | succeeded | -1.7932712731 | 6.3335 | 3 | — |
| 6 | succeeded | -1.7607363044 | 6.48526 | 3 | — |
| 7 | succeeded | -1.8286033906 | 6.8852 | 3 | — |
| 8 | succeeded | -1.8094314058 | 6.62473 | 3 | — |
| 9 | succeeded | -1.8270451462 | 6.56486 | 3 | — |
| 10 | succeeded | -1.8400882812 | 6.38579 | 3 | — |
| 11 | succeeded | -1.8301269484 | 6.93164 | 3 | — |
| 12 | succeeded | -1.8378969916 | 6.46011 | 3 | — |
| 13 | succeeded | -1.8293123252 | 6.37968 | 3 | — |
| 14 | succeeded | -1.8273866146 | 6.36492 | 3 | — |
| 15 | succeeded | -1.8382151433 | 7.13362 | 3 | — |
| 16 | succeeded | -1.8269107446 | 6.31857 | 3 | — |
| 17 | succeeded | -1.8374384649 | 6.30998 | 3 | — |
| 18 | succeeded | -1.8368021614 | 6.5906 | 3 | — |
| 19 | succeeded | -1.8311675768 | 6.46384 | 3 | — |
| 20 | succeeded | -1.8265730775 | 6.58866 | 3 | — |
| 21 | succeeded | -1.8368027044 | 6.49141 | 3 | — |