mshqc 1.0.0

Python bindings for MSH-QC quantum mechanics library

MSHQC - Modern Quantum Chemistry Library

A high-performance quantum chemistry library implementing modern electronic structure methods with Python bindings.

🌟 Features

Electronic Structure Methods

• Self-Consistent Field (SCF)

  • Restricted Hartree-Fock (RHF)
  • Unrestricted Hartree-Fock (UHF)
  • Restricted Open-shell Hartree-Fock (ROHF)
  • DIIS convergence acceleration
  • Cholesky Unrestricted Hartree-Fock (CD-UHF)
  • Cholesky Restricted Open-shell Hartree-Fock (CD-ROHF)
  • Cholesky Restricted Hartree-Fock (CD-RHF)

• Møller-Plesset Perturbation Theory

  • MP2, MP3 (Restricted and Unrestricted)
  • Orbital-Optimized MP2/MP3 (OMP2/OMP3)
  • Cholesky Unrestricted MP2/MP3 (CD-UMP2/CD-UMP3)
  • Cholesky Orbital-Optimized MP2/MP3 (CD-OMP2/CD-OMP3)
  • Cholesky Restricted MP2/MP3 (CD-RMP2/CD-CD-RMP3)

• Multi-Configurational Self-Consistent Field (MCSCF)

  • Complete Active Space SCF (CASSCF)
  • State-Averaged CASSCF (SA-CASSCF)
  • Complete Active Space Perturbation Theory 2nd order (CASPT2)
  • Cholesky Decomposition Complete Active Space SCF (CD-CASSCF)
  • Cholesky Decomposition Complete Active Space Perturbation Theory 2nd order (CD-CASPT2)
  • Cholesky Decomposition-State-Averaged-CASSCF (CD-SA-CASSCF)
  • Cholesky Decomposition-State Average-Complete Active Space Perturbation Theory 2nd order (CD-SA-CASPT2)
  • Cholesky Decomposition-State Average-Complete Active Space Perturbation Theory 3rd order (CD-SA-CASPT3)

• Configuration Interaction (CI) (in progress)

  • Configuration Interaction Singles (CIS)
  • Configuration Interaction Singles and Doubles (CISD)
  • Configuration Interaction Singles, Doubles, and Triples (CISDT)
  • Full Configuration Interaction (FCI)
  • Multireference CI (MRCI)
  • CIPSI (Configuration Interaction by Perturbation with Selection Iteratively)

Advanced Features

• Integral Transformations

  • Cholesky decomposition for electron repulsion integrals (ERI)
  • Electron Repulsion Integral Four-Index Transformation

• Gradient and Optimization

  • Analytical gradients for SCF methods
  • Numerical gradients
  • Geometry optimization

• Analysis Tools

  • Natural orbitals
  • Transition density matrices
  • Wavefunction analysis
  • One-particle density matrices (OPDM)

📋 Prerequisites

Required Dependencies

• C++ Compiler: GCC 7+ or Clang 5+ (C++17 support)
• CMake: 3.15 or higher
• Python: 3.8 or higher
• Libint2: For integral evaluation
• Eigen3: For linear algebra operations
• pybind11: For Python bindings
• NumPy: For Python interface

Optional Dependencies

• OpenMP: For parallel computation
• MKL/OpenBLAS: For optimized linear algebra

Installation Binding Python

Using Conda (Cross-Platform)

# Create conda environment
conda create -n mshqc python=3.11
conda activate mshqc

# Install dependencies via conda-forge
conda install -c conda-forge \
    cmake \
    eigen \
    libint \
    numpy \
    pybind11

# Clone and install
git clone https://github.com/syahrulhidayat/mshqc.git
cd mshqc
pip install -e .