    # Set color of selected atoms to "standard" colors.

    # store current selection
    DefPropAtom 'prev_sel' 'selected'

    # make carbons dark grey
    SelectAtom 'prev_sel & name = "C*"'
    ColorAtom 0.3 0.3 0.3

    # make oxygens red
    SelectAtom 'prev_sel & name = "O*"'
    ColorAtom 1 0 0

    # make nitrogens blue
    SelectAtom 'prev_sel & name = "N*"'
    ColorAtom 0 0 1

    # make sulfurs yellow
    SelectAtom 'prev_sel & name = "S*"'
    ColorAtom 1 1 0

    # make hydrogens light grey
    SelectAtom 'prev_sel & name = "H*"'
    ColorAtom 0.9 0.9 0.9

    # restore previous selection
    SelectAtom 'prev_sel'