Your first calculation, in a few lines.

1 Install

git clone ssh://git@gitlab.peintinger.com:26/mpei/vibeqc.git
cd vibeqc
./scripts/install.sh

install.sh builds the native core, creates a virtualenv and installs vibe-qc. It accepts --dev (track main) and --branch NAME; see the installation guide for the full surface and the manual native-deps recipe.

The repository is currently private (public once the JCC release paper is out). Email mpei@vibe-qc.com with a public SSH key to request read-only clone access — see the installation guide for details.

2 Run RHF on water

import vibeqc as vq
import numpy as np

mol = vq.Molecule([
    vq.Atom(8, [ 0.0,  0.00,  0.00]),
    vq.Atom(1, [ 0.0,  1.43, -0.98]),
    vq.Atom(1, [ 0.0, -1.43, -0.98]),
])
basis = vq.BasisSet(mol, "6-31g*")
result = vq.run_rhf(mol, basis)

eps = np.asarray(result.mo_energies)
homo = mol.n_electrons() // 2 - 1
print(f"E(SCF)  = {result.energy:.6f} Ha")
print(f"ε(HOMO) = {eps[homo]*27.211386:.2f} eV")
print(f"gap     = {(eps[homo+1] - eps[homo])*27.211386:.2f} eV")

3 Read the result

You get the SCF energy in hartree and the HOMO energy plus HOMO–LUMO gap in eV. Swap run_rhf for run_rks, run_mp2, or a periodic driver to go further — same front-end, same objects.