Hyperfine tensor and defect structure of T center

## About the datasetThis record provides all data to reproduce the hyperfine coupling analysis of a T center defect in silicon. The results are reported in "Long-lived entanglement of a spin-qubit register in silicon photonics". DOI: https://doi.org/10.48550/arXiv.2504.15467 ## Files included- **hyperfine_terms.npz**: NumPy archive containing three float arrays (`Fermi_contact`, `Dipolar`, `Hyperfine`) saved via `numpy.savez`.- **POSCAR**: VASP format structure file specifying a 1002‑atom silicon supercell with a T center defect. ## Computational methods- Electronic structure calculations were performed with VASP using the HSE06 screened hybrid functional. ## Usage & reuse1. **Load hyperfine data in Python** ```python import numpy as np data = np.load('hyperfine_terms.npz') Fc = data['Fermi_contact'] Dip = data['Dipolar'] Hf = data['Hyperfine']2. **Load defect structures using pymatgen** ```python from pymatgen.io.vasp import Poscar poscar = Poscar.from_file('POSCAR') structure = poscar.structure