quichem
Utilities for fast input of chemical formulae and equations.
...Entering data does not require any modifier keys or keystrokes to be pressed.
This SourceForge page provided pre-built Windows binaries of quichem-pyside. **To run quichem on Mac OS X or Linux**, or with the wxPython front-end, please download the source from quichem's GitHub page at: github.com/spamalot/quichem.