[Chimera-users] Quantification of electron density volume

Hi everyone, I am wondering if there is a way to extract the values plotted under Tools > Volume Data > Values at Atom Positions? Specifically, I would like to quantify the electron density surrounding a domain and compare it to another domain. This can be easily done if the values in the Histogram plotted under the tool mentioned above can be tabulated on a per-atom basis (perhaps within a PDB file, in the B-factor column). If anyone knows other methods to achieve this goal, that would be helpful as well. Thank you very much in advance for your feedback and suggestions! Best regards, Priyamvada