Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 40
- Best energy (Ha)
- -1.03717
LiH
BeyondH2 hardware VQE and fixed-parameter remeasurement · hardware · ibm_phoenix
Final energy-1.0293211709hartree
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_phoenix
- Resource type
- quantum processor
- Processor family
- Nighthawk
- Processor model
- ibm_phoenix
- Processor revision
- 2
- Qubits
- 120
- Connectivity
- Not recorded
- Runtime execution
- single-job
- Shots
- 1024
- Precision
- 0.03125
- Resilience
- 0
- Submitted
- 2026-09-09T17:12:59+00:00
- Wall time (s)
- 11954.5
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
- 2
- Physical qubits
- 2
- Parameters
- 1
- Depth
- 43
- Two-qubit gates
- 4
- Hamiltonian terms
- 9
Scientific provenance
- Cohort
- post hoc phoenix
- Reference method
- CASCI
- Reference energy (Ha)
- -1.0532229194242344
- Energy convention
- Qiskit Nature active-space qubit Hamiltonian; nuclear and inactive-space constants excluded
- Absolute error (Ha)
- 0.0239017
- Signed error (Ha)
- 0.0239017
- Total QPU time (s)
- 57
- Calibration time
- 2026-09-09T16:48:22+00:00
- Mean readout error
- 0.024658203125
- Mean two-qubit gate error
- 0.0015216700737894773
Software
- Qiskit
- 2.5.2
- Qiskit Aer
- 0.17.2
- Qiskit Algorithms
- 0.4.0
- Qiskit Ibm Runtime
- 0.49.0
- Qiskit Nature
- 0.7.2
Molecular geometry (angstrom)
| Atom | x | y | z |
|---|---|---|---|
| Li | 0 | 0 | 0 |
| H | 0 | 0 | 1.6204 |
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
19 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 | -1.0355287263 | 31.5031 | 3 | [0.0] |
| 2 | succeeded | -0.5644695649 | 214.121 | 3 | [1.0] |
| 3 | succeeded | -0.6042844302 | 31.432 | 3 | [-1.0] |
| 4 | succeeded | -0.8749842972 | 122.522 | 3 | [0.5] |
| 5 | succeeded | -1.0075211186 | 31.1718 | 3 | [-0.25] |
| 6 | succeeded | -1.0248305557 | 91.9413 | 3 | [0.1] |
| 7 | succeeded | -1.0341106542 | 607.179 | 3 | [-0.10000000000000002] |
| 8 | succeeded | -1.0205293239 | 851.51 | 3 | [0.05] |
| 9 | succeeded | -1.0350200846 | 1457.81 | 3 | [-0.025] |
| 10 | succeeded | -1.0338601959 | 4948.95 | 3 | [0.010000000000000002] |
| 11 | succeeded | -0.9744834078 | 1063.32 | 3 | [-0.010000000000000002] |
| 12 | succeeded | -1.0324363756 | 91.9019 | 3 | [0.005000000000000001] |
| 13 | succeeded | -1.0261024272 | 31.6905 | 3 | [-0.0025000000000000005] |
| 14 | succeeded | -1.0371710965 | 32.0861 | 3 | [0.001] |
| 15 | succeeded | -1.0196361059 | 31.1549 | 3 | [0.002] |
| 16 | succeeded | -1.0202276275 | 31.4868 | 3 | [0.0005] |
| 17 | succeeded | -1.0321190788 | 31.4729 | 3 | [0.00125] |
| 18 | succeeded | -1.0225426713 | 2186.63 | 3 | [0.0009] |
| 19 | succeeded | -1.0293211709 | 61.9456 | 3 | [0.0011] |
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-597A1D3097FEA7CF | 1024 | 0 | 10 | -1.0402453790 | -1.0427211634 | -1.0381368622 | 1.2 |
| theta_final | EPOCH-597A1D3097FEA7CF | 1024 | 0 | 10 | -1.0394663825 | -1.0418539100 | -1.0367336182 | 1.2 |
Means below combine the displayed measurements descriptively. Inspect epochs and replicates in the download before drawing statistical conclusions.