Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 40
- Best energy (Ha)
- -4.90808
O2
BeyondH2 hardware VQE and fixed-parameter remeasurement · hardware · ibm_aachen
Final energy-4.8732939936hartree
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
- 2026-08-01T17:10:42+00:00
- Wall time (s)
- 1186.41
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)
- 0.489355
- Signed error (Ha)
- 0.489355
- Total QPU time (s)
- 150
- Calibration time
- 2026-08-01T16:24:21+00:00
- Mean readout error
- 0.00762939453125
- 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
25 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 | -4.8655213613 | 30.4935 | 6 | [0.0] |
| 2 | succeeded | -4.0644901692 | 181.099 | 6 | [1.0] |
| 3 | succeeded | -4.0480778315 | 30.5765 | 6 | [-0.9999999999999999] |
| 4 | succeeded | -4.5429784941 | 30.5047 | 6 | [0.5] |
| 5 | succeeded | -4.8321551509 | 30.5689 | 6 | [-0.25] |
| 6 | succeeded | -4.8813473993 | 30.5101 | 6 | [0.09999999999999999] |
| 7 | succeeded | -4.7596573321 | 30.4924 | 6 | [0.3] |
| 8 | succeeded | -4.8718957581 | 30.6278 | 6 | [-2.7755575615628914e-17] |
| 9 | succeeded | -4.8470421224 | 60.7634 | 6 | [0.15] |
| 10 | succeeded | -4.8768190379 | 30.5263 | 6 | [0.0875] |
| 11 | succeeded | -4.8592720346 | 30.4857 | 6 | [0.125] |
| 12 | succeeded | -4.8625738200 | 30.4718 | 6 | [0.08999999999999998] |
| 13 | succeeded | -4.8280790371 | 30.4588 | 6 | [0.11] |
| 14 | succeeded | -4.8711022257 | 271.297 | 6 | [0.09499999999999999] |
| 15 | succeeded | -4.8844132852 | 30.4956 | 6 | [0.10124999999999999] |
| 16 | succeeded | -4.8701943311 | 30.483 | 6 | [0.10375] |
| 17 | succeeded | -4.8168858163 | 30.4904 | 6 | [0.10024999999999999] |
| 18 | succeeded | -4.8956684889 | 30.5021 | 6 | [0.10225] |
| 19 | succeeded | -4.9080833084 | 30.4548 | 6 | [0.10325] |
| 20 | succeeded | -4.8944947169 | 30.4715 | 6 | [0.10525] |
| 21 | succeeded | -4.8357403571 | 30.4993 | 6 | [0.10225] |
| 22 | succeeded | -4.8578928509 | 30.4831 | 6 | [0.10375] |
| 23 | succeeded | -4.8597610533 | 30.5544 | 6 | [0.103] |
| 24 | succeeded | -4.8388543143 | 30.4761 | 6 | [0.10335] |
| 25 | succeeded | -4.8732939936 | 30.5427 | 6 | [0.10314999999999999] |
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 | -4.7811418293 | -4.8060062608 | -4.7675251131 | 38.5 |
| theta_best | EPOCH-BC7F9D3C329056D0 | 1024 | 0 | 10 | -4.7652459749 | -4.8172818051 | -4.7364056351 | 42.5 |
| theta_final | EPOCH-981D79BDF527D935 | 1024 | 0 | 10 | -4.7881440651 | -4.8226713806 | -4.7272481125 | 38.5 |
| theta_final | EPOCH-BC7F9D3C329056D0 | 1024 | 0 | 10 | -4.7617668129 | -4.7901003321 | -4.7232422221 | 42.5 |
Means below combine the displayed measurements descriptively. Inspect epochs and replicates in the download before drawing statistical conclusions.