Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 40
- Best energy (Ha)
- -1.04339
LiH
BeyondH2 hardware VQE and fixed-parameter remeasurement · hardware · ibm_phoenix
Final energy-1.0411283393hartree
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
- 2026-09-10T15:16:33+00:00
- Wall time (s)
- 699.978
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)
- 0.0120946
- Signed error (Ha)
- 0.0120946
- 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 | -1.0338396707 | 31.457 | 3 | [0.0] |
| 2 | succeeded | -0.5563777153 | 31.9879 | 3 | [1.0] |
| 3 | succeeded | -0.6030656487 | 31.9455 | 3 | [-1.0] |
| 4 | succeeded | -0.8909163969 | 32.0425 | 3 | [0.5] |
| 5 | succeeded | -1.0054771860 | 31.3608 | 3 | [-0.25] |
| 6 | succeeded | -1.0311512373 | 31.6982 | 3 | [0.1] |
| 7 | succeeded | -1.0361088409 | 31.7041 | 3 | [-0.1] |
| 8 | succeeded | -1.0006381398 | 31.9402 | 3 | [-0.30000000000000004] |
| 9 | succeeded | -1.0433862211 | 32.0731 | 3 | [1.3877787807814457e-17] |
| 10 | succeeded | -1.0267774817 | 31.4526 | 3 | [0.10000000000000002] |
| 11 | succeeded | -1.0376682960 | 31.3235 | 3 | [-0.04999999999999999] |
| 12 | succeeded | -1.0357183330 | 31.2011 | 3 | [0.025000000000000015] |
| 13 | succeeded | -1.0405283919 | 31.7424 | 3 | [-0.009999999999999988] |
| 14 | succeeded | -1.0400010607 | 31.3122 | 3 | [0.010000000000000016] |
| 15 | succeeded | -1.0378763720 | 31.6095 | 3 | [-0.004999999999999987] |
| 16 | succeeded | -1.0364172055 | 31.3614 | 3 | [0.0025000000000000144] |
| 17 | succeeded | -1.0366116717 | 31.1609 | 3 | [-0.0009999999999999861] |
| 18 | succeeded | -1.0378029121 | 31.5329 | 3 | [0.001000000000000014] |
| 19 | succeeded | -1.0406910100 | 31.4443 | 3 | [-0.0004999999999999861] |
| 20 | succeeded | -1.0403897680 | 31.4554 | 3 | [0.0002500000000000139] |
| 21 | succeeded | -1.0397390521 | 31.3137 | 3 | [-9.999999999998613e-05] |
| 22 | succeeded | -1.0411283393 | 31.4028 | 3 | [0.00010000000000001387] |
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 | -1.0398199149 | -1.0431703063 | -1.0382432334 | 1.2 |
| theta_final | EPOCH-597A1D3097FEA7CF | 1024 | 0 | 10 | -1.0397837138 | -1.0433676065 | -1.0379197021 | 1.2 |
Means below combine the displayed measurements descriptively. Inspect epochs and replicates in the download before drawing statistical conclusions.