Crate integral_core 

integral-core — Layer 1 (integral engines) + Layer 2 (operator/derivative layer).

• os — the one-electron Obara–Saika engine (overlap, kinetic, nuclear-attraction, and multipole/dipole integrals).
• os_eri — the OS/HGP two-electron (ERI) engine.
• rys — the Rys-quadrature ERI engine.
• operator — the L2 one-electron operator DSL over r and p.
• deriv — geometric (nuclear-coordinate) first derivatives.

See ARCHITECTURE.md (L1/L2).

Modules

deriv

Geometric (nuclear-coordinate) first derivatives of integrals (L2).

operator

One-electron operator DSL over polynomials in r and p (L2).

os

One-electron integrals by Obara–Saika (OS) recurrence.

os_eri

Two-electron repulsion integrals (ERIs) by the Obara–Saika / Head-Gordon–Pople (OS/HGP) recurrence — the second ERI engine (see ARCHITECTURE.md, L1).

rys

Two-electron repulsion integrals (ERIs) by Rys quadrature.