Software
- ChemOffice Professional
Commercial software for drawing molecular structures, 3D models and many more. High price but most higher education institutes will provide students/staff with free institutional licenses. The molecular sketcher now has a free online version (built using HTML$5$ and JS): ChemDraw online - MarvinSketch (desktop) & MarvinJS (web)
Freeware (closed-source) for drawing molecular structures with a wide feature set. In addition to just being able to draw Lewis structures, the software includes plugins to name what you have drawn (systematic/traditional), predict properties, change atom and bond properties, generate stereoisomers, and much more. Desktop version is Java based so works on Mac, Windows, Linux. - ChemDoodle
Commercial software for 2D and 3D molecular structures and diagrams and much more. Also has versions for tablet/mobile. An online free version of ChemDoodle is here: ChemDoodle Web Components - ACD/ChemSketch
Commercial software for Windows only. Includes a free version with fewer features. - chemfig
Free $\mathrm\LaTeX$ package distributed under the LATEX Project Public License 1.3c developed by Christian Tellechea for creating 2D chemical structures with seamless integration into any type of a document, from a standalone illustration to a textbook or a poster. Since TikZ is used for graphics generation, the functionality ofchemfigcan be greatly extended. PDF output can also be rasterized by using external tools such as ImageMagick. Also, see chemfig questions on TeX.SE. - Avogadro
Free, open source software for generating 3D models and computational chemistry. - GAMESS
Free ab initio molecular quantum chemistry program. - OrcaORCA
Free for academic use ab initio/DFT quantum chemistry program. Has a nice tutorial on basic molecular modelling here. - Open Babel: The Open Source Chemistry Toolbox
Free "Open Babel is a chemical toolbox designed to speak the many languages of chemical data. It's an open, collaborative project allowing anyone to search, convert, analyze, or store data from molecular modeling, chemistry, solid-state materials, biochemistry, or related areas." - RDKit: Open-Source Cheminformatics Software
- Odyssey by Wavefunction
Commercial software designed to be used for teaching and learning chemistry. Includes high quality molecular simulations of many materials, in-built virtual labs. Excellent animations of many physical and chemical processes.
