Hi everybody, I am trying to get a list of all hydrogen atoms within certain distance from a specific atom. I found an old thread suggesting using findclash for that. When I use: findclash #0.265:4@c overlap -8 hbond 0 ignoreIntraRes false log true bondSeparation 0 everything works fine and I get the list of all the atoms within the desired distance limits. However, I get all types of atoms. To select only for contacts to hydrogens, I have tried to add the "test" option but when I type: findclash #0.265:4@c overlap -8 hbond 0 ignoreIntraRes false log true bondSeparation 0 test @H the procedure does not report on any contacts. Am I misunderstanding the syntax? What is the way to get only the distances between :4@c and all hydrogens within ~10A? Moreover, I am ultimately interested in the sum of all reported distances (or more specifically sum of (1/r)^6 where r is the distance). Is there simple way to get this value calculated in Chimera (e.g. simple script)? Unfortunately, I have no idea about Python coding, so right now I have to import the list to Excel and calculate what I need in there (which is fine for a few atoms but slightly tedious when you have to check several hundred of them...). Any help would be appreciated. Thanks, Józef