ChemJuice Grande!

Marvin is a great alternative to the subscription based ChemDraw by CambridgeSoft. It is a collection of tools for drawing, displaying and characterizing chemical structures, substructures and reactions.It will also convert structures you create to various molecular visualiztion formats, such as .pdb and .mol, compatible with programs such as PyMOL and SwissPDB Viewer.

ACD/ChemSketch is a chemically intelligent drawing interface that allows you to draw almost any chemical structure including organics, organometallics, polymers, and Markush structures. Use it to produce professional looking structures and diagrams for reports and publications.

Avogadro is a free, fantastically easy to use molecule editor.

The Gnome Chemistry Utils include six chemistry related programs: - GChemPaint, a 2D chemical formula editor. - a chemical calculator (computes raw formule, molar weight, mass composition and isotopic pattern). - a molecule 3d viewer using OpenGL to display molecular models. - a crystal structure editor and viewer. - a periodic table of the elements. - a spectrum viewer.

BKChem is a free (as in free software :o) chemical drawing program. It was conceived and written by Beda Kosata and is currently maintained by Reinis Danne.

Cool Chemistry Tool - educational app for Students.Chemist will help you in chemical tasks! Use the Periodic Table just like a computer keyboard. With the Chemist you will learn everything you need to know about the elements, compounds and chemical reactions.

Ghemical is computational chemistry package, which is licensed under GNU GPL . The ghemical authors are listed here .

XDrawChem is a free software program for drawing chemical structural formulas, available for Unix and Mac OS. It is distributed under the GNU GPL. In Microsoft Windows this program is called WinDrawChem.Major features Fixed length and fixed angle drawing Automatic alignment of figures Detection of structures, text, and arrows, and their automatic placement Can automatically draw rings and other structures - has all standard amino acids and nucleic acids in a built-in library Retrieval of structures from a network database based on CAS number, formula, or name Retrieval of information on a molecule based on a drawing Symbols such as partial charge and radicals Reading MDL Molfiles, CML (Chemical Markup Language), ChemDraw binary format, ChemDraw XML text format Writing MDL Molfiles, CML, ChemDraw XML text format Integration with OpenBabel, allowing XDrawChem to read and write over 20 different chemical file formats. Image export in Portable Network Graphics (PNG), Windows bitmap, Encapsulated PostScript (EPS), and Scalable Vector Graphics (SVG) 3D structure generation with the help of the external program BUILD3D Simple spectra predictions, including 13C-NMR, 1H-NMR (based on additive rules and functional group lookup methods), and IR Simple property estimation, including pKa, octanol-water partition coefficient, and gas-phase enthalpy change. »

Communicate with the natural language of chemical structures, biological pathways, and models