Hi Sudheer, Chimera isn't able to compute hydrodynamic radius of maps or molecules. Are you primarily interested in diffusion properties or optical properties of your structure? Do you think the hydrodynamic radius for a uniform solid bounded by a contour surface of your map would be useful? Do you mean Stokes' radius or the R_H defined on the wikipedia page? http://en.wikipedia.org/wiki/Hydrodynamic_radius The latter looks like a pretty simple calculation. Tom -------- Original Message -------- Subject: [Chimera-users] Hydrodynamic radius From: Sudheer To: chimera users Date: 10/14/09 1:05 PM

Hi,

Can I measure the Hydrodynamic radius a Cryo-EM density map using Chimera?

Thank you, Sudheer Molugu. ------------------------------------------------------------------------