Ghemical is a computational chemistry software package, Ghemical relies on external code to provide the quantum-mechanical calculations. Semi-empirical methods MNDO, MINDO/3, AM1 and PM3 come from the MOPAC7 package, and are included in the source distribution. The MPQC package (GNU GPL) is used to provide ab initio methods. WWW: https://www.bioinformatics.org/ghemical/ghemical/index.html