1. A GNOME molecular modelling environment Ghemical is a computational chemistry software package written in C++. It has a graphical user interface and it supports both quantum- mechanics (semi-empirical) models and molecular mechanics models. Geometry optimization, molecular dynamics and a large set of visualization tools using OpenGL are currently available. 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 (Public Domain), and are included in the package. The project started as a freeware molecular modelling package, but since the graphical user interface part of the package is quite advanced and clearly written (according to our own biased view, at least), the package now aims to become a common framework for molecular modelling programs generally. From Debian 3.0r0 APT