Model parameters for the ambient-pressure organic Dirac electron state in α-(BETS)₂AuCl₂

Dataset for α-(BETS)₂AuCl₂: Electronic Structure and Physical Properties

Project Overview

This dataset supports a theoretical and experimental study on the organic conductor α-(BETS)₂AuCl₂, where BETS stands for bis(ethylenedithio)tetraselenafulvalene. The study involves x-ray diffraction measurements, ab initio calculations using Quantum ESPRESSO, downfolding calculations using RESPACK, Wannier function calculations using Wannier90, and many-body calculations using H-wave.

About

This repository provides a comprehensive dataset related to the theoretical and experimental study of the organic conductor α-(BETS)₂AuCl₂. The data includes:

• Crystal structure data (CIF format)
• Experimental electrical resistivity measurements
• Ab initio electronic structure calculations (with and without spin-orbit interaction)
• Wannier function calculations
• Fermi surface and band dispersion analysis

License

• CC BY 4.0

Folder Structures

• LICENSE
• README.md
• cif
  • 2433895.cif: Crystal structure data from CCDC (measured at 150 K)
• data
  • experiments
    • BETS2AuCl2_in-plane.csv: In-plane resistivity data
    • BETSAuCl2_out-of-plane.csv: Out-of-plane resistivity data
  • non-soi (Calculations without spin-orbit interaction)
  • soi (Calculations with spin-orbit interaction)

Non-SOI Directory Structure

The non-soi directory contains calculations without spin-orbit interaction:

• qe/ (Quantum ESPRESSO):

  • scf_relax.in, scf_relax.out: Input/output files for relaxation calculation
  • scf.in, scf.out: Input/output files for SCF calculation
  • band.in, band.out: Input/output files for band calculation
  • bands.in, bands.out: Input/output files for bands calculation
  • nscf.in, nscf.out: Input/output files for NSCF calculation
  • aucl2.band.gnu: Band structure data for plotting

• respack/ (RESPACK):

  • respack.in: Input file for RESPACK
  • calc_wan.out: Output file for Wannier calculation
  • dat.iband: Output file of bands obtained by Wannier calculation
  • dir-intW/: Directory containing bare and screened long-range Coulomb interactions
  • dir-model/: Directory containing effective models

• wannier90/ (Wannier90):

  • aucl2.win: Wannier90 input file
  • aucl2.wout: Wannier90 output file
  • aucl2_hr.dat: Hamiltonian in Wannier basis
  • pw2wan.in, pw2wan.out: Interface files between QE and Wannier90

• hwave/ (H-wave):

  • input.toml: H-wave input file
  • fermi_energy.dat: Calculated Fermi energy
  • band_dispersion.pdf: Band dispersion plot
  • FermiSurface_mod_orb*.pdf: Fermi surface plots for each orbital
  • output/: Output files and plots

SOI Directory Structure

The soi directory contains calculations with spin-orbit interaction:

• qe/ (Quantum ESPRESSO):

  • scf.in, scf.out: Input/output files for SCF calculation (with SOI)
  • scf_relax.out: Output file for relaxation calculation
  • band.in, band.out: Input/output files for band calculation
  • bands.in, bands.out: Input/output files for bands calculation
  • nscf.in, ncf.out: Input/output files for NSCF calculation
  • aucl2.band.gnu: Band structure data for plotting

• wannier90/ (Wannier90):

  • aucl2.win: Wannier90 input file
  • wan90.out: Wannier90 output file
  • aucl2_hr.dat: Hamiltonian in Wannier basis
  • pw2wan.in: Interface file between QE and Wannier90

• hwave/ (H-wave):

  • input.toml: H-wave input file
  • fermi_energy.dat: Calculated Fermi energy
  • energy.dat: Energy eigenvalues
  • dir-model/: Effective model data
  • output/: Output files and plots

Experimental Data

The experiments directory contains temperature-dependent electrical resistivity measurements:

• Measurement conditions:

  • Temperature range: ~2 K to 300 K
  • Applied magnetic fields: 0, 2.5, 5, 9 kOe

• Data files:

  • BETS2AuCl2_in-plane.csv: In-plane resistivity (ρ∥)
  • BETSAuCl2_out-of-plane.csv: Out-of-plane resistivity (ρ⊥)

Usage Instructions

To use this data, you will need the following software:

• Quantum ESPRESSO
• RESPACK
• Wannier90
• H-wave

Steps to Reproduce Calculations

1. Set Up Quantum ESPRESSO:

   • Use the provided .in files for SCF, relaxation, band, and NSCF calculations.
   • Run the calculations using Quantum ESPRESSO with the appropriate input files.
   • For SOI calculations, ensure you use fully relativistic pseudopotentials.

2. Run Wannier90 Calculations:

   • Use the pw2wan.in file to interface with Quantum ESPRESSO.
   • Run Wannier90 using the aucl2.win input file.
   • Obtain the Wannier Hamiltonian (aucl2_hr.dat).

3. Run RESPACK Calculations (Non-SOI only):

   • Use the respack.in file to set up RESPACK.
   • Perform the downfolding calculations and obtain the effective models.

4. Run H-wave Calculations:

   • Use the input.toml file to configure H-wave.
   • Calculate the Fermi surface and band dispersion.

5. Analyze Results:

   • Use the output files to analyze the electronic structure and band calculations.
   • Refer to the .gnu files for plotting the band structures with gnuplot.
   • Compare non-SOI and SOI results to understand the effect of spin-orbit coupling.

Crystal Structure

• Material: α-(BETS)₂AuCl₂
• CCDC Number: 2433895
• Space Group: P-1 (triclinic)
• Measurement Temperature: 150 K
• Lattice Parameters:
  • a = 9.0953(5) Å
  • b = 10.7799(6) Å
  • c = 17.2891(9) Å
  • α = 103.632(2)°
  • β = 96.748(2)°
  • γ = 90.767(2)°

Physical Properties

Property	In-plane (ρ∥)	Out-of-plane (ρ⊥)	Anisotropy (ρ⊥/ρ∥)
ρ at 300 K	~0.025 Ω·cm	~1.16 Ω·cm	~46
ρ at 2 K	~0.064 Ω·cm	~4.26 Ω·cm	~67

Citations and References

When using this dataset, please cite the following paper (T.B.A.):

Contact

For questions or comments, please contact:

• k-yoshimi__at__issp.u-tokyo.ac.jp
• tkobayashi__at__mail.saitama-u.ac.jp

Please replace at with @.

Version History

• v1.0.0 (2026-01-08): Initial release