[Telamond]

Does anyone know any free computer programs that lets you draw molecules and curly arrows for mechanisms?

[azmanam]

ISISDraw.  It's not great, but it's free and will get the job done.  You'll draw a curved arrow, then 2-D rotate to get the start and end where you want them.

Like I said, not perfect, but you get what you pay for.

http://www.mdli.com/products/framework/isis_draw/index.jsp

[kryptoniitti]

Chemsketch is also worth checking. It's very versatile and has also curly arrows drawing function in its repertoire (it takes a little practice to get them look the way you want though).

http://www.acdlabs.com/download/chemsk.html

[Telamond]

Thanks for the help on both the programs!
ISISDraw is a bit complicated, Chemsketch is a lot easier for me to understand. Just, I don't know how to make the curle arrows for the reaction mechanisms, could you help me out with a screenshot maybe? ^^;

[kryptoniitti]

Here you go, the relevant buttons are highlighted in red:

Click, hold down and twist, click, hold down and twist etc. When you are done, right-click and thats it.

If want simpler curly arrows, try the two buttons above the highlighted, this tip was for those more complex curly arrows.

[Telamond]

Thanks a lot!
It reminds a whole lot like the pen function on Photoshop!