Drawing structural formulas is a very common task in chemistry. Simple chemical formulas are often not sufficient, they are ambiguous for pretty much any non-trivial molecule, and structural formulas are pretty much required to explain reaction mechanisms accurately.
So while we can write formulas like $\ce{C6H12O6}$ natively on the site, drawing the following structural formula is not as easy
To draw such formulas you need either have a local pogram installed, or copy an existing image from somewhere, you can't draw them here.
I think it would be very useful to have a tool for drawing structural formulas embedded in the site. I'd like to collect our requirements here, as well as collect information about existing libraries that could be used on the site.
The must-have features are
- drawing of a single chemical formula
- drawing of a reaction (A -> B)
Other features that would be useful are
- the ability to save the result as png, so that viewers that don't edit don't have to load the javascript and there is no delay in display
- Users should be able to copy the formulas from another post and user them in their own posts (an answer would likely need some of the same formulas the question uses)
If you have some more ideas on what such a libray should be able to do, please comment on this post.
The main purpose of this post is to find libraries that could be added to the site. Please add one answer for each library that could be implemented. It should not only be the name, but also a short evaluation of the features and maybe your own impression of the library.