I am a graduate student at Indiana University, and I am trying to use ChimeraX to visualize positively charged surface accessible residues on some protein models. I've been trying to find the right combination of commands to get this to work but haven't been successful. I know how to calculate surface accessible residues, how to color the surface accessibility of residues within a selection on my model, and even how to calculate hydrophobicity of residues (related to charge), but I cannot figure out how to model the charge of surface exposed residues. Could you please point me in the right direction so I can get the models that I would like?