Open Babel is a chemical toolbox designed to speak the many languages of chemical data. It allows one to search, convert, analyze, or store data from molecular modeling, chemistry, solid-state materials, biochemistry, or related areas. Features include:

* Hydrogen addition and deletion * Support for Molecular Mechanics * Support for SMARTS molecular matching syntax * Automatic feature perception (rings, bonds, hybridization, aromaticity) * Flexible atom typer and perception of multiple bonds from atomic coordinates * Gasteiger-Marsili partial charge calculation

File formats Open Babel supports include PDB, XYZ, CIF, CML, SMILES, MDL Molfile, ChemDraw, Gaussian, GAMESS, MOPAC and MPQC.

This package includes the following utilities: * obabel: Convert between various chemical file formats * obenergy: Calculate the energy for a molecule * obminimize: Optimize the geometry, minimize the energy for a molecule * obgrep: Molecular search program using SMARTS pattern * obgen: Generate 3D coordinates for a molecule * obprop: Print standard molecular properties * obfit: Superimpose two molecules based on a pattern * obrotamer: Generate conformer/rotamer coordinates * obconformer: Generate low-energy conformers * obchiral: Print molecular chirality information * obrotate: Rotate dihedral angle of molecules in batch mode * obprobe: Create electrostatic probe grid