Method
- Mapper
- PT
- Ansatz
- UCC
- Optimizer
- COBYLA
- Maximum iterations
- 40
- Best energy (Ha)
- -1.04276
LiH
BeyondH2 hardware VQE and fixed-parameter remeasurement · hardware · ibm_phoenix
Final energy-1.0407200800hartree
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
- 2026-09-10T15:43:54+00:00
- Wall time (s)
- 1217.62
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)
- 0.0125028
- Signed error (Ha)
- 0.0125028
- Total QPU time (s)
- 63
- 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
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 | -1.0402886054 | 62.6342 | 3 | [0.0] |
| 2 | succeeded | -0.5552970564 | 183.065 | 3 | [1.0] |
| 3 | succeeded | -0.6094178240 | 31.6747 | 3 | [-1.0] |
| 4 | succeeded | -0.8657588592 | 122.257 | 3 | [0.5] |
| 5 | succeeded | -1.0176149362 | 31.6318 | 3 | [-0.24999999999999997] |
| 6 | succeeded | -1.0360068053 | 31.1615 | 3 | [0.10000000000000002] |
| 7 | succeeded | -1.0346783668 | 31.6673 | 3 | [-0.10000000000000002] |
| 8 | succeeded | -1.0374719335 | 125.689 | 3 | [0.05] |
| 9 | succeeded | -1.0363630776 | 31.7471 | 3 | [-0.025000000000000005] |
| 10 | succeeded | -1.0392580818 | 31.5454 | 3 | [0.010000000000000002] |
| 11 | succeeded | -1.0370907505 | 31.2666 | 3 | [-0.010000000000000002] |
| 12 | succeeded | -1.0390770414 | 31.5325 | 3 | [0.005000000000000001] |
| 13 | succeeded | -1.0427644467 | 122.289 | 3 | [-0.002500000000000001] |
| 14 | succeeded | -1.0386057909 | 31.6012 | 3 | [-0.0075000000000000015] |
| 15 | succeeded | -1.0412023400 | 31.5836 | 3 | [-4.336808689942018e-19] |
| 16 | succeeded | -1.0381101380 | 31.3641 | 3 | [-0.003500000000000001] |
| 17 | succeeded | -1.0420144438 | 31.9353 | 3 | [-0.001500000000000001] |
| 18 | succeeded | -1.0353622343 | 122.525 | 3 | [-0.003000000000000001] |
| 19 | succeeded | -1.0392258374 | 31.7366 | 3 | [-0.002250000000000001] |
| 20 | succeeded | -1.0384835226 | 31.5776 | 3 | [-0.0026000000000000007] |
| 21 | succeeded | -1.0407200800 | 31.6146 | 3 | [-0.002400000000000001] |
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 | -1.0405915259 | -1.0427886622 | -1.0378693874 | 1.2 |
| theta_final | EPOCH-597A1D3097FEA7CF | 1024 | 0 | 10 | -1.0404413593 | -1.0429299823 | -1.0382274945 | 1.2 |
Means below combine the displayed measurements descriptively. Inspect epochs and replicates in the download before drawing statistical conclusions.