Entry C4H6_ccpvdz_JW_ADAPT_v4_tapered__sha256_d70625e50afebe76 | QEncode

VQE Gap

2.8286e-3 Ha

CASCI ref

-154.921897 Ha

Qubits (tapered)

CCSD(T) corr.

-6.258e-1 Ha

Molecule / Problem

NameC4H6

Basis setcc-pvdz

GeometryC 0.0 0.0 0.6695; C 0.0 0.0 -0.6695; C 0.0 1.2288 1.3978; C 0.0 -1.2288 -1.3978; H 0.0 2.1501 0.8386; H 0.0 1.2396 2.4742; H 0.0 -2.1501 -0.8386; H 0.0 -1.2396 -2.4742; H 0.0 0.9217 -1.2788; H 0.0 -0.9217 1.2788

Charge0

Spin0

Active electrons4

Active orbitals4

Orbital optimizationHF

Encoding / Circuit

Qubit mappingjordan-wigner

Ansatz typeadapt

Ansatz reps (HEA)1

TaperingZ2 symmetry — 4 symmetries removed

Qubits (original)8

Qubits (tapered)4

Num parameters1

Circuit depth20

2Q gates14

Energy Results

HF energy-154.8993843213 Ha

MP2 energy-155.4569210310 Ha

CCSD energy-155.5000626191 Ha

CCSD(T) energy-155.5252019040 Ha

CASCI ground state-154.9218973816 Ha

VQE best energy-154.9190688030 Ha

|VQE − CASCI| gap2.828579e-3 Ha

CCSD(T) correlation-6.258176e-1 Ha

Optimizer / Run Config

AlgorithmADAPT-VQE (COBYLA inner)

Multistart runs1

Max iterations500

Total func evals21

Num parameters1

Backenddefault.qubit

Provenance / Reproducibility

Entry IDC4H6_ccpvdz_JW_ADAPT_v4_tapered__sha256_d70625e50afebe76

Schema version4.0.0

Created (UTC)2026-07-16T09:36:26.872827+00:00

SHA-256 hashd70625e50afebe765148ad8dff340d4b96ae89854d9a892f61c7fffe3155a828

Python3.11.15

PySCF2.6.2

PennyLane0.45.0

OpenFermion1.6.1

NumPy2.2.6

SciPy1.13.1

Reproduce this result

# Clone repo and install pinned environment

git clone https://github.com/qencode-benchmark/qencode-benchmark

cd qencode-benchmark

pip install -r requirements-v4.txt

# Run this entry

python scripts/generate_entry_v4.py \

--molecule C4H6 \

--mapping jordan_wigner \

--ansatz-type adapt \

--reps 1 \

--multistart 1 \

--max-iter 500 \

--out-dir releases/v4/db

View raw JSON on GitHub