Module eht 

Extended Hückel Theory (EHT) module.

Implements a semiempirical electronic-structure calculation pipeline:

• Phase B1: EHT parameters, Slater-type orbitals, STO-nG Gaussian expansions
• Phase B2: Overlap matrix S and Hamiltonian matrix H
• Phase B3: Generalized eigenproblem solver (Löwdin orthogonalization)
• Phase B4: 3D volumetric mapping of molecular orbitals
• Phase B5: Output structures for rendering (raw volumes + Marching Cubes)

Re-exports

pub use basis::AtomicOrbital;

pub use basis::GaussianPrimitive;

pub use basis::SlaterOrbital;

pub use hamiltonian::build_hamiltonian;

pub use marching_cubes::marching_cubes;

pub use marching_cubes::IsosurfaceMesh;

pub use overlap::build_overlap_matrix;

pub use params::EhtParams;

pub use params::OrbitalDef;

pub use solver::solve_eht;

pub use solver::EhtResult;

pub use volume::evaluate_orbital_on_grid_parallel;

pub use volume::evaluate_orbital_on_grid;

pub use volume::VolumetricGrid;

Modules

basis

Atomic orbital basis representations: STO and contracted Gaussian (STO-nG).

hamiltonian

Hamiltonian matrix H construction using EHT (Extended Hückel Theory).

marching_cubes

Marching Cubes isosurface extraction from volumetric grids.

overlap

Overlap matrix S construction using STO-3G Gaussian integrals.

params

EHT parameter tables: VSIP values and Slater exponents per element/orbital.

solver

Generalized eigenproblem solver for EHT: HC = SCE.

volume

3D volumetric mapping of molecular orbitals.