Dialog Box: Select Mode [Dialog Bar, Atoms window; Setting menu]
The dialog allows selection of the vibrational mode which appears in the Atoms window.
The mode is selected by double-clicking on the desired line in the list box, or by clicking the Select Mode button - simply selecting a line with a single-click does not set the mode. The selected mode is written out below the list box.
Secondary atoms are atoms outside the primitive unit cell which are needed to show all bonds and angles (i.e., those bonds and angles which cross unit-cell boundaries) in crystals and polymers. Secondary atoms are not used in molecules. If present, they may be marked with a triangle, or omitted entirely.