chemistry

• Chemtool
  Chemtool is a GTK+-based 2D chemical structure editor for X11. Drawings can be exported in XFig format for further annotation, or as Postscript files (using xfig's companion program transfig). A set ...
  
• KMol
  KMol calculates molecular weights and elemental compositon of compounds from their chemical formula. KMol supports user defined groups, unlimited number of nested subgroups, multicomponent compounds,...
  
• Chemistry Development Kit
  The Chemistry Development Kit (CDK) classes are Java utitility classes for chemoinformatics and computational chemistry. They are a complete re-write of the CompChem classes that were the basis of JC...
  
• Jmol
  Jmol is a Free, Open Source molecule viewer and editor. It is a measurement tool for chemical scientists. ...
  
• JOELib
  JOELib is a cheminformatics library which supports SMARTS substructure search, descriptor calculation, processing/filtering pipes, and conversion of different chemical file formats. ...
  
• BKchem
  BKchem is a free chemical drawing program. BKchem is written in Python, an interpreted and very nice programming language. ...
  

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