RustiQ

RustiQ is an experimental Rust quantum chemistry application and reusable rustiq-chem-core library. RustiQ-authored source is licensed under MIT OR Apache-2.0. Executables include LGPL libraries, third-party notices and access to corresponding sources. See distribution terms. It supports RHF, UHF, MP2, XYZ geometries, Gaussian basis sets, TOML/Nickel inputs, sequential studies, versioned JSON output, and portable .rustiq bundles with reuse of atomic-orbital electron-repulsion integrals (AO ERIs).

Do not use results for research conclusions without independent validation against established quantum chemistry packages.

Purpose

RustiQ explores what modern Rust software engineering can bring to quantum chemistry through strong typing, memory safety, explicit error handling, modularity, and maintainability. These engineering goals go hand in hand with scientific correctness, numerical validation, and performance; RustiQ does not claim superiority over mature quantum chemistry packages or established Fortran implementations.

Quick start

For a prebuilt executable, see installation and the first H₂ calculation. Release archives contain the executable and licenses; obtain basis data and create calculation inputs as shown in those guides.

To build from source, install Git, Rust through rustup, a C/C++ build toolchain, and CMake; see manual setup. Alternatively, enter nix develop .#rust after cloning:

git clone https://github.com/mveril/RustiQ.git
cd RustiQ
cargo build --locked
cargo run --locked -- basis import tests/data/sto-3g.json
cargo run --locked -- run samples/h2/sto-3g/calculation.toml

The checked-in basis fixture avoids online basis downloads for this first calculation. Run these commands from the repository root.

The product is called RustiQ; its Cargo packages are rustiq-chem (CLI) and rustiq-chem-core (library). The executable is rustiq (rustiq.exe on Windows), and the Rust library import remains rustiq_core. To install from this checkout: cargo install --locked --path ..

Documentation

• RustiQ manual: installation, first H₂ calculation, output interpretation, and development.
• Book sources for reading the manual from a checkout.
• Portable bundles: save, rerun, inspect, verify, and reuse calculation snapshots and compatible AO ERIs.
• Scientific scope and reference comparisons: validated cases, tolerances, limitations, and reproducible reports.
• Contributing, roadmap, and persistence V1 specification.
• Generate the Rust API reference with tools/generate-rustdoc.sh --open, or .\tools\generate-rustdoc.ps1 -Open on Windows.

Build with nix build .#book, or preview inside nix develop .#rust after running mdbook-mermaid install docs, using mdbook serve docs --open. Without Nix, install mdbook and mdbook-mermaid using Cargo and run the same asset installation and preview commands. See documentation checks for coverage.