Quick Start

For a complete worked example — from input construction through execution, HDF5 output inspection, and post-processing — see the graphene GW tutorial.

1. Prepare qassemble.in

QAssemble reads input from a restricted declarative input file named qassemble.in. Below is a minimal example for a graphene-like two-site model with GW:

{
    "Crystal": {
        "RVec": [[1, 0, 0], [0.5, 0.866, 0], [0, 0, 1]],
        "SOC": False,
        "CorF": "F",
        "Basis": [
            [[0.33333, 0.33333, 0], 1],
            [[0.66667, 0.66667, 0], 1],
        ],
        "NSpin": 1,
        "NElec": 2,
        "KGrid": [25, 25, 1],
    },
    "Hamiltonian": {
        "OneBody": {
            "Hopping": {
                ((0, 0), (1, 0)): {
                    1.0: [[0, 0, 0], [-1, 0, 0], [0, -1, 0]],
                },
            },
            "Onsite": {
                0: {(0, 0): 0.0, (1, 0): 0.0},
            },
        },
        "TwoBody": {
            "Local": {
                "Parameter": "SlaterKanamori",
                "option": {
                    (0, (0,)): {"l": 0, "U": 2.0, "Up": 0.0},
                    (1, (0,)): {"l": 0, "U": 2.0, "Up": 0.0},
                },
            },
            "NonLocal": {
                ((0, 0), (1, 0)): {
                    0.20: [[0, 0, 0], [-1, 0, 0], [0, -1, 0]],
                },
            },
        },
    },
    "Control": {
        "Method": "gw",
        "Prefix": "my_calc",
        "NSCF": 20000,
        "Mix": 0.1,
        "T": 2000,
        "MatsubaraCutOff": 100,
        "ConstantW": 1.0,
    },
}

2. Run

CLI (recommended)Module execution

qassemble

qassemble graphene_gw.in

python -m QAssemble
python -m QAssemble graphene_gw.in

Directory Structure

QAssemble/
├── pyproject.toml              # Package configuration and dependencies
├── README.md
└── src/
    ├── QAssemble.py            # Legacy entry point (backward compatible)
    └── QAssemble/
        ├── __init__.py         # Package exports and version
        ├── __main__.py         # python -m QAssemble support
        ├── CLI.py              # CLI entry point (qassemble command)
        ├── Run.py              # Run class (input parsing and execution)
        ├── Crystal.py          # Lattice geometry, k-point grids, index mappings
        ├── CorrelationFunction.py  # Top-level workflow coordinator (TB / HF / GW)
        ├── FLatStc.py          # Static fermionic lattice (Hamiltonian, HF self-energy)
        ├── FLatDyn.py          # Dynamic fermionic lattice (Green's functions via DLR)
        ├── FPathStc.py         # Static fermionic path
        ├── FPathDyn.py         # Dynamic fermionic path
        ├── BLatStc.py          # Static bosonic lattice (bare/screened Coulomb)
        ├── BLatDyn.py          # Dynamic bosonic lattice (polarization, screened W)
        ├── BLocStc.py          # Static bosonic local site
        ├── BPathStc.py         # Static bosonic path
        ├── BPathDyn.py         # Dynamic bosonic path
        └── utility/
            ├── DLR.py          # Discrete Lehmann Representation transforms
            ├── Dyson.py        # Dyson equation solver
            ├── Fourier.py      # Lattice Fourier transforms
            ├── Common.py       # Shared utilities
            ├── Bare.py         # Bare Green's functions
            └── Mixing.py       # Mixing parameter control