Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 40
- Best energy (Ha)
- -1.85946
H2
BeyondH2 hardware VQE and fixed-parameter remeasurement · hardware · ibm_pittsburgh
Final energy-1.8240269270hartree
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
- 2026-07-30T20:14:07+00:00
- Wall time (s)
- 17644.8
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)
- 0.0256351
- Signed error (Ha)
- 0.0256351
- Total QPU time (s)
- 69
- Calibration time
- 2026-07-30T18:47:42+00:00
- Mean readout error
- 0.010009765625
- 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 | -1.8111806649 | 2132.53 | 3 | [0.0] |
| 2 | succeeded | -0.5455173126 | 3289.39 | 3 | [1.0] |
| 3 | succeeded | -0.9477247029 | 2709.73 | 3 | [-1.0] |
| 4 | succeeded | -1.2801419489 | 3227.98 | 3 | [0.5] |
| 5 | succeeded | -1.8399654951 | 427.782 | 3 | [-0.25] |
| 6 | succeeded | -1.6896790666 | 31.8008 | 3 | [-0.5] |
| 7 | succeeded | -1.8402162966 | 1704.33 | 3 | [-0.14999999999999997] |
| 8 | succeeded | -1.8226290995 | 884.942 | 3 | [-0.04999999999999995] |
| 9 | succeeded | -1.8555632030 | 154.435 | 3 | [-0.19999999999999996] |
| 10 | succeeded | -1.8093674722 | 366.697 | 3 | [-0.29999999999999993] |
| 11 | succeeded | -1.8460084678 | 123.492 | 3 | [-0.14999999999999997] |
| 12 | succeeded | -1.8429218931 | 154.369 | 3 | [-0.22499999999999995] |
| 13 | succeeded | -1.8485953499 | 398.231 | 3 | [-0.18999999999999995] |
| 14 | succeeded | -1.8504814078 | 32.3535 | 3 | [-0.20999999999999996] |
| 15 | succeeded | -1.8308779761 | 92.937 | 3 | [-0.19499999999999995] |
| 16 | succeeded | -1.8365495225 | 184.754 | 3 | [-0.20249999999999996] |
| 17 | succeeded | -1.8419817297 | 275.818 | 3 | [-0.19949999999999996] |
| 18 | succeeded | -1.8380870787 | 154.367 | 3 | [-0.20099999999999996] |
| 19 | succeeded | -1.8594597643 | 123.285 | 3 | [-0.19949999999999996] |
| 20 | succeeded | -1.8269814147 | 367.899 | 3 | [-0.19899999999999995] |
| 21 | succeeded | -1.8423340522 | 428.735 | 3 | [-0.19974999999999996] |
| 22 | succeeded | -1.8314696377 | 245.961 | 3 | [-0.19939999999999997] |
| 23 | succeeded | -1.8240269270 | 123.775 | 3 | [-0.19959999999999994] |
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 | -1.8304743471 | -1.8417423905 | -1.8111520091 | 5.625 |
| theta_best | EPOCH-2B4918A2E64142FB | 1024 | 0 | 7 | -1.8176124507 | -1.8256793769 | -1.7995733978 | 6.125 |
| theta_best | EPOCH-5882C2993A675671 | 1024 | 0 | 3 | -1.8274109697 | -1.8353661991 | -1.8129212630 | 2.625 |
| theta_best | EPOCH-DE16026B7C747E84 | 1024 | 1 | 3 | -1.8514089337 | -1.8622417265 | -1.8418355226 | 6 |
| theta_best | EPOCH-EB7658141BD7F934 | 1024 | 2 | 3 | -1.8429694325 | -1.8575829015 | -1.8284836339 | 9.375 |
| theta_final | EPOCH-0D3257EA32142E89 | 1024 | 0 | 10 | -1.8329080196 | -1.8645396491 | -1.8194219000 | 5.625 |
| theta_final | EPOCH-2B4918A2E64142FB | 1024 | 0 | 7 | -1.8071837902 | -1.8235520694 | -1.7967414454 | 6.125 |
| theta_final | EPOCH-5882C2993A675671 | 1024 | 0 | 3 | -1.8304024816 | -1.8380813476 | -1.8229604077 | 2.625 |
| theta_final | EPOCH-DE16026B7C747E84 | 1024 | 1 | 3 | -1.8478801761 | -1.8502023081 | -1.8437669018 | 6 |
| theta_final | EPOCH-EB7658141BD7F934 | 1024 | 2 | 3 | -1.8534765333 | -1.8614660844 | -1.8378237604 | 9.375 |
Means below combine the displayed measurements descriptively. Inspect epochs and replicates in the download before drawing statistical conclusions.