How to save and/or export electron density surfaces?


I’m trying to make some visualisations of electron density clouds around molecules. This is what I do: I use avogadro 1.2 to draw molecules (Library 1.2.0, Babel 2.3.2, Qt 4.8.7, Win.10), then I export structures to Gaussian (09W), compute orbitals and obtain the *.FChk file. After that I open it with Avogadro and create several electron density surfaces from gaussian data with different iso-values to get something like this:

DNA (G-C) clouds-bs

But after that i get several problems:

  1. How do I save my surfaces? If I close the *.FChk file (even after saving) and then reopen it, all my surfaces have disappeared and I need to redraw them, which takes quite a bit of time at high quality. I suspect that there should be some file format that saves surfaces, but I can’t find it.

  2. How can I save a high resolution picture? The best I can now get out of Avogadro is the kind of picture I have posted. Its maximum resolution is about 1200x800, which is way too small if I want to print it on a poster, for example. Maybe there are some tutorials on how to do it with the Export function?

  3. Is there a way to export my 3D-model to some fornat supported by other 3D-visualisation/design software? VRML only exports one surface, and I want to export the model the way it’s shown above.