# Bending arrows in Tikz

In Tikz, I would like to bend an arrow like the one between $H_2O$ and $O_2$ in this figure:

I'm able to have a bended line between $H_2O$ and $O_2$, but it's not touching the photophosphorylation node…

How can I do that?

• Fow on #latex found the beginning of a solution : pastebin.tlhiv.org/DExfrO7T . The problem is that the arrow is "broken" when it touches the circle. – Bjonnh Jan 22 '12 at 15:57
• Hey, cool diagram. Post the code, please. – Faheem Mitha Jan 22 '12 at 16:34

This is most easily done by using the nodes placement, and a to command. You will then be able to achieve the desired result.
\begin{tikzpicture}