Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 40
- Best energy (Ha)
- -1.04029
LiH
BeyondH2 hardware VQE and fixed-parameter remeasurement · hardware · ibm_phoenix
Final energy-1.0286757081hartree
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
- 2026-09-10T15:28:13+00:00
- Wall time (s)
- 940.66
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)
- 0.0245472
- Signed error (Ha)
- 0.0245472
- Total QPU time (s)
- 66
- Calibration time
- 2026-09-10T03:48:45+00:00
- Mean readout error
- 0.0106201171875
- 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
22 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 | -1.0294242817 | 31.6754 | 3 | [0.0] |
| 2 | succeeded | -0.5644507526 | 31.308 | 3 | [1.0] |
| 3 | succeeded | -0.6024275263 | 31.6256 | 3 | [-1.0] |
| 4 | succeeded | -0.8767599263 | 31.3338 | 3 | [0.49999999999999994] |
| 5 | succeeded | -1.0016705165 | 31.8275 | 3 | [-0.24999999999999997] |
| 6 | succeeded | -1.0096089359 | 31.7222 | 3 | [0.1] |
| 7 | succeeded | -1.0265835169 | 31.43 | 3 | [-0.09999999999999999] |
| 8 | succeeded | -1.0367160516 | 31.3786 | 3 | [0.05000000000000001] |
| 9 | succeeded | -0.9985279114 | 31.3264 | 3 | [0.15000000000000002] |
| 10 | succeeded | -1.0402901860 | 31.3818 | 3 | [0.0] |
| 11 | succeeded | -1.0372360529 | 31.7471 | 3 | [-0.05000000000000001] |
| 12 | succeeded | -1.0281349704 | 31.472 | 3 | [0.025] |
| 13 | succeeded | -1.0368110772 | 31.4289 | 3 | [-0.005000000000000001] |
| 14 | succeeded | -1.0377908437 | 31.2818 | 3 | [0.010000000000000002] |
| 15 | succeeded | -1.0394274914 | 31.69 | 3 | [-0.005000000000000001] |
| 16 | succeeded | -1.0332163096 | 92.1085 | 3 | [0.0025000000000000005] |
| 17 | succeeded | -1.0355371596 | 31.4472 | 3 | [-0.001] |
| 18 | succeeded | -1.0383977902 | 61.5894 | 3 | [0.001] |
| 19 | succeeded | -1.0351312741 | 61.7407 | 3 | [-0.0005] |
| 20 | succeeded | -1.0343334385 | 31.4866 | 3 | [0.00025] |
| 21 | succeeded | -1.0379116293 | 31.3169 | 3 | [-9.999999999999999e-05] |
| 22 | succeeded | -1.0286757081 | 153.09 | 3 | [9.999999999999999e-05] |
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 | -1.0390140190 | -1.0427208787 | -1.0358028627 | 1.2 |
| theta_final | EPOCH-597A1D3097FEA7CF | 1024 | 0 | 10 | -1.0406207719 | -1.0451289848 | -1.0374826379 | 1.2 |
Means below combine the displayed measurements descriptively. Inspect epochs and replicates in the download before drawing statistical conclusions.