Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 40
- Best energy (Ha)
- -4.88446
O2
BeyondH2 hardware VQE and fixed-parameter remeasurement · hardware · ibm_aachen
Final energy-4.8750009850hartree
Shots1024
Runtime executionsingle-job
Resilience0
MappingPT
Active space4e4o
Parity mapping with full symmetry tapering · Shots and precision · Resilience settings
Execution
- Mode
- hardware
- Provider
- IBM Quantum
- Compute resource
- ibm_aachen
- Resource type
- quantum processor
- Processor family
- Heron
- Processor model
- ibm_aachen
- Processor revision
- 3
- Qubits
- 156
- Connectivity
- Not recorded
- Runtime execution
- single-job
- Shots
- 1024
- Precision
- 0.03125
- Resilience
- 0
- Submitted
- 2026-08-01T13:10:09+00:00
- Wall time (s)
- 1637.18
Molecular system
- Charge
- 0
- Multiplicity
- 3
- Basis
- sto3g
- Active space
- 4e4o
- Active electrons
- 4
- Spatial orbitals
- 4
- Active orbital indices
- Not recorded
- Geometry units
- angstrom
Circuit
- Logical qubits
- 4
- Physical qubits
- 4
- Parameters
- 1
- Depth
- 74
- Two-qubit gates
- 12
- Hamiltonian terms
- 50
Scientific provenance
- Cohort
- primary heron
- Reference method
- CASCI
- Reference energy (Ha)
- -5.362649434129489
- Energy convention
- Qiskit Nature active-space qubit Hamiltonian; nuclear and inactive-space constants excluded
- Absolute error (Ha)
- 0.487648
- Signed error (Ha)
- 0.487648
- Total QPU time (s)
- 138
- Calibration time
- 2026-08-01T11:56:48+00:00
- Mean readout error
- 0.011688232421875
- Mean two-qubit gate error
- 0.0021541457335317316
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
Molecular geometry (angstrom)
| Atom | x | y | z |
|---|---|---|---|
| O | 0 | 0 | 0 |
| O | 0 | 0 | 1.216 |
Dataset publication
Associated articles
- The winner's curse in hardware VQE: drift-differenced remeasurement of finite-shot selection bias DOI 10.48550/arXiv.2609.27704 arXiv 2609.27704 published preprint
Compute access
- Fraunhofer Quantum Now and EQeS · IBM Quantum · allocation: Fraunhofer Quantum Now
Optimization trajectory
23 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 | -4.8419040453 | 60.66 | 6 | [0.0] |
| 2 | succeeded | -3.9983517351 | 90.7889 | 6 | [1.0] |
| 3 | succeeded | -4.0866983660 | 151.176 | 6 | [-1.0] |
| 4 | succeeded | -4.5821565608 | 60.5528 | 6 | [0.5] |
| 5 | succeeded | -4.8107928302 | 60.6022 | 6 | [-0.25] |
| 6 | succeeded | -4.8154369556 | 90.8929 | 6 | [0.1] |
| 7 | succeeded | -4.8380483337 | 90.9606 | 6 | [-0.1] |
| 8 | succeeded | -4.8714856108 | 60.6567 | 6 | [0.05000000000000001] |
| 9 | succeeded | -4.8346230498 | 60.5274 | 6 | [0.15000000000000002] |
| 10 | succeeded | -4.8721249388 | 60.5627 | 6 | [0.0] |
| 11 | succeeded | -4.8599920946 | 60.5477 | 6 | [-0.025000000000000005] |
| 12 | succeeded | -4.8544617160 | 30.4475 | 6 | [0.005000000000000001] |
| 13 | succeeded | -4.8498470794 | 60.7208 | 6 | [-0.010000000000000004] |
| 14 | succeeded | -4.8124604338 | 90.7447 | 6 | [0.005000000000000002] |
| 15 | succeeded | -4.8801419534 | 90.6939 | 6 | [-0.0012500000000000002] |
| 16 | succeeded | -4.8546293057 | 90.7328 | 6 | [-0.003750000000000001] |
| 17 | succeeded | -4.8832466562 | 60.6051 | 6 | [-0.0002500000000000002] |
| 18 | succeeded | -4.8670948509 | 30.4615 | 6 | [0.00075] |
| 19 | succeeded | -4.8676309649 | 60.5358 | 6 | [-0.0007500000000000002] |
| 20 | succeeded | -4.8844305203 | 60.5351 | 6 | [-2.168404344971009e-19] |
| 21 | succeeded | -4.8844583200 | 60.6213 | 6 | [0.0002499999999999998] |
| 22 | succeeded | -4.8420839228 | 60.5809 | 6 | [0.0003499999999999998] |
| 23 | succeeded | -4.8750009850 | 90.7154 | 6 | [0.0001499999999999998] |
Independent fixed-parameter remeasurements
These measurements reevaluate saved parameter vectors without running the optimizer. They are kept separate from the optimization trajectory.
| Vector | Epoch | Shots | Resilience | Measurements | Mean energy (Ha) | Minimum (Ha) | Maximum (Ha) | Allocated QPU time (s) |
|---|---|---|---|---|---|---|---|---|
| theta_best | EPOCH-981D79BDF527D935 | 1024 | 0 | 10 | -4.8104420265 | -4.8415261365 | -4.7833331981 | 38.5 |
| theta_best | EPOCH-BC7F9D3C329056D0 | 1024 | 0 | 10 | -4.7829070481 | -4.8013381255 | -4.7626558034 | 42.5 |
| theta_final | EPOCH-981D79BDF527D935 | 1024 | 0 | 10 | -4.8052626656 | -4.8395774290 | -4.7892373866 | 38.5 |
| theta_final | EPOCH-BC7F9D3C329056D0 | 1024 | 0 | 10 | -4.7923895723 | -4.8124585876 | -4.7650053040 | 42.5 |
Means below combine the displayed measurements descriptively. Inspect epochs and replicates in the download before drawing statistical conclusions.