Object selection

The mouse left button allows to select object(s) and display atomic label(s):

The first click on any atom/bond will select this atom/bond, the selection is highlighted / covered in light blue color [Fig. 5.20-b], a second click and the atom(s) label(s) will be added to the representation [Fig. 5.20-c], finally a third click will unselect the atom(s) and remove the label(s) [Fig. 5.20-a].