Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 40
- Best energy (Ha)
- -1.86703
H2
BeyondH2 hardware VQE and fixed-parameter remeasurement · hardware · ibm_pittsburgh
Final energy-1.8567522575hartree
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
- 2026-08-02T18:02:47+00:00
- Wall time (s)
- 1420.51
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)
- 0.00709021
- Signed error (Ha)
- -0.00709021
- Total QPU time (s)
- 63
- Calibration time
- 2026-08-02T17:28:21+00:00
- Mean readout error
- 0.0067138671875
- 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
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 | -1.8065699067 | 546.694 | 3 | [0.0] |
| 2 | succeeded | -0.4843289083 | 31.215 | 3 | [1.0] |
| 3 | succeeded | -0.9181912889 | 31.3981 | 3 | [-0.9999999999999999] |
| 4 | succeeded | -1.2423405545 | 31.1209 | 3 | [0.49999999999999994] |
| 5 | succeeded | -1.8449247550 | 31.2198 | 3 | [-0.24999999999999994] |
| 6 | succeeded | -1.6655816806 | 61.6767 | 3 | [-0.4999999999999999] |
| 7 | succeeded | -1.8670250102 | 31.2481 | 3 | [-0.14999999999999994] |
| 8 | succeeded | -1.8395212036 | 62.0813 | 3 | [-0.04999999999999992] |
| 9 | succeeded | -1.8250896256 | 31.1049 | 3 | [-0.19999999999999996] |
| 10 | succeeded | -1.8377366666 | 61.6174 | 3 | [-0.13749999999999993] |
| 11 | succeeded | -1.8653706500 | 61.6389 | 3 | [-0.17499999999999993] |
| 12 | succeeded | -1.8375049690 | 31.407 | 3 | [-0.13999999999999993] |
| 13 | succeeded | -1.8464737736 | 31.2234 | 3 | [-0.15999999999999995] |
| 14 | succeeded | -1.8467150232 | 30.979 | 3 | [-0.14499999999999993] |
| 15 | succeeded | -1.8504909598 | 61.7858 | 3 | [-0.15249999999999994] |
| 16 | succeeded | -1.8510826214 | 31.2254 | 3 | [-0.14899999999999994] |
| 17 | succeeded | -1.8644285762 | 61.4352 | 3 | [-0.15099999999999994] |
| 18 | succeeded | -1.8522602136 | 31.6383 | 3 | [-0.14949999999999994] |
| 19 | succeeded | -1.8592337978 | 61.7944 | 3 | [-0.15024999999999994] |
| 20 | succeeded | -1.8431688739 | 61.7387 | 3 | [-0.14989999999999995] |
| 21 | succeeded | -1.8567522575 | 31.2205 | 3 | [-0.15009999999999993] |
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 | -1.8365175379 | -1.8496618692 | -1.8228493348 | 5.625 |
| theta_best | EPOCH-2B4918A2E64142FB | 1024 | 0 | 7 | -1.8257712686 | -1.8443541076 | -1.7982847328 | 6.125 |
| theta_best | EPOCH-5882C2993A675671 | 1024 | 0 | 3 | -1.8243485932 | -1.8363178248 | -1.8183630222 | 2.625 |
| theta_best | EPOCH-DE16026B7C747E84 | 1024 | 1 | 3 | -1.8455624832 | -1.8610771969 | -1.8261972567 | 6 |
| theta_best | EPOCH-EB7658141BD7F934 | 1024 | 2 | 3 | -1.8539674823 | -1.8552751311 | -1.8520844373 | 9.375 |
| theta_final | EPOCH-0D3257EA32142E89 | 1024 | 0 | 10 | -1.8382657234 | -1.8483655626 | -1.8285247021 | 5.625 |
| theta_final | EPOCH-2B4918A2E64142FB | 1024 | 0 | 7 | -1.8328066856 | -1.8379683643 | -1.8259225369 | 6.125 |
| theta_final | EPOCH-5882C2993A675671 | 1024 | 0 | 3 | -1.8175779607 | -1.8302958663 | -1.7999410034 | 2.625 |
| theta_final | EPOCH-DE16026B7C747E84 | 1024 | 1 | 3 | -1.8521216998 | -1.8690897779 | -1.8412486770 | 6 |
| theta_final | EPOCH-EB7658141BD7F934 | 1024 | 2 | 3 | -1.8344652292 | -1.8452366129 | -1.8279219560 | 9.375 |
Means below combine the displayed measurements descriptively. Inspect epochs and replicates in the download before drawing statistical conclusions.