Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 40
- Best energy (Ha)
- -1.86053
H2
BeyondH2 hardware VQE and fixed-parameter remeasurement · hardware · ibm_pittsburgh
Final energy-1.8339569093hartree
Shots1024
Runtime executionsingle-job
Resilience0
MappingPT
Active space2e2o
Parity mapping with full symmetry tapering · Shots and precision · Resilience settings
Execution
- Mode
- hardware
- Provider
- IBM Quantum
- Compute resource
- ibm_pittsburgh
- Resource type
- quantum processor
- Processor family
- Heron
- Processor model
- ibm_pittsburgh
- Processor revision
- 3
- Qubits
- 156
- Connectivity
- Not recorded
- Runtime execution
- single-job
- Shots
- 1024
- Precision
- 0.03125
- Resilience
- 0
- Submitted
- 2026-08-01T17:54:27+00:00
- Wall time (s)
- 725.03
Molecular system
- Charge
- 0
- Multiplicity
- 1
- Basis
- sto3g
- Active space
- 2e2o
- Active electrons
- 2
- Spatial orbitals
- 2
- Active orbital indices
- Not recorded
- Geometry units
- angstrom
Circuit
- Logical qubits
- 1
- Physical qubits
- 1
- Parameters
- 1
- Depth
- 5
- Two-qubit gates
- 0
- Hamiltonian terms
- 3
Scientific provenance
- Cohort
- primary heron
- Reference method
- CASCI
- Reference energy (Ha)
- -1.8496620506001422
- Energy convention
- Qiskit Nature active-space qubit Hamiltonian; nuclear and inactive-space constants excluded
- Absolute error (Ha)
- 0.0157051
- Signed error (Ha)
- 0.0157051
- Total QPU time (s)
- 69
- Calibration time
- 2026-08-01T17:31:23+00:00
- Mean readout error
- 0.0052490234375
- 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
Molecular geometry (angstrom)
| Atom | x | y | z |
|---|---|---|---|
| H | 0 | 0 | 0 |
| H | 0 | 0 | 0.7428 |
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 | -1.8110581297 | 31.6652 | 3 | [0.0] |
| 2 | succeeded | -0.5080720615 | 31.1755 | 3 | [1.0] |
| 3 | succeeded | -0.9298867042 | 31.0236 | 3 | [-1.0000000000000002] |
| 4 | succeeded | -1.2423405545 | 31.3306 | 3 | [0.5] |
| 5 | succeeded | -1.8326414988 | 31.0474 | 3 | [-0.25000000000000006] |
| 6 | succeeded | -1.7984877746 | 31.1595 | 3 | [-0.3500000000000001] |
| 7 | succeeded | -1.8436418211 | 31.4342 | 3 | [-0.15000000000000008] |
| 8 | succeeded | -1.8312513128 | 31.1243 | 3 | [-0.05000000000000007] |
| 9 | succeeded | -1.8554463989 | 31.4316 | 3 | [-0.20000000000000007] |
| 10 | succeeded | -1.8221217653 | 31.1209 | 3 | [-0.3000000000000001] |
| 11 | succeeded | -1.8605281941 | 31.0219 | 3 | [-0.15000000000000005] |
| 12 | succeeded | -1.8339626404 | 31.4351 | 3 | [-0.10000000000000003] |
| 13 | succeeded | -1.8384394012 | 31.1044 | 3 | [-0.17500000000000004] |
| 14 | succeeded | -1.8436418211 | 31.1899 | 3 | [-0.14500000000000005] |
| 15 | succeeded | -1.8529705897 | 31.2261 | 3 | [-0.16000000000000006] |
| 16 | succeeded | -1.8421061753 | 31.3248 | 3 | [-0.14500000000000005] |
| 17 | succeeded | -1.8332522643 | 31.1649 | 3 | [-0.15250000000000005] |
| 18 | succeeded | -1.8428165514 | 31.4563 | 3 | [-0.14900000000000005] |
| 19 | succeeded | -1.8297061150 | 31.5122 | 3 | [-0.15100000000000005] |
| 20 | succeeded | -1.8448251445 | 31.4326 | 3 | [-0.14950000000000005] |
| 21 | succeeded | -1.8545062356 | 31.0953 | 3 | [-0.15025000000000005] |
| 22 | succeeded | -1.8579336704 | 31.3298 | 3 | [-0.14990000000000006] |
| 23 | succeeded | -1.8339569093 | 31.8214 | 3 | [-0.15010000000000004] |
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-0D3257EA32142E89 | 1024 | 0 | 10 | -1.8351122869 | -1.8576943312 | -1.8187191654 | 5.625 |
| theta_best | EPOCH-2B4918A2E64142FB | 1024 | 0 | 7 | -1.8280988116 | -1.8405705295 | -1.8171816092 | 6.125 |
| theta_best | EPOCH-5882C2993A675671 | 1024 | 0 | 3 | -1.8339939336 | -1.8529725001 | -1.8200154720 | 2.625 |
| theta_best | EPOCH-DE16026B7C747E84 | 1024 | 1 | 3 | -1.8597492602 | -1.8670143093 | -1.8466251003 | 6 |
| theta_best | EPOCH-EB7658141BD7F934 | 1024 | 2 | 3 | -1.8402286393 | -1.8516549893 | -1.8195467056 | 9.375 |
| theta_final | EPOCH-0D3257EA32142E89 | 1024 | 0 | 10 | -1.8360924585 | -1.8500180125 | -1.8209613666 | 5.625 |
| theta_final | EPOCH-2B4918A2E64142FB | 1024 | 0 | 7 | -1.8314890532 | -1.8517872664 | -1.8063095532 | 6.125 |
| theta_final | EPOCH-5882C2993A675671 | 1024 | 0 | 3 | -1.8335216231 | -1.8370282009 | -1.8314734585 | 2.625 |
| theta_final | EPOCH-DE16026B7C747E84 | 1024 | 1 | 3 | -1.8626206128 | -1.8740046073 | -1.8489549419 | 6 |
| theta_final | EPOCH-EB7658141BD7F934 | 1024 | 2 | 3 | -1.8532385275 | -1.8624168274 | -1.8467499311 | 9.375 |
Means below combine the displayed measurements descriptively. Inspect epochs and replicates in the download before drawing statistical conclusions.