subroutine char SEGMENTS
 delete atom select segment name #* end
 key old select all end

 symm select segment name SEGMENTS end around center atom $1 dist 20. neigh 2
 key SYMM_M select .not old end
 image select SYMM_M end col 105 bond
 image select SYMM_M .a .not by bond all end col 105 atom cros
 
return

 key old select all end
 symm select segm name SOL end around center atom $1 dist 20. neigh 2
 key SYMM_WAT select .not old end
 image select SYMM_WAT .and. atom name O* end col 125 atom cros
 return