S(1) since this molecule has point-group symmetry 2/m, while the second molecule has only point-group symmetry m as will be seen in a subsequent page. The higher symmetry of S(1) is indicated by the fact that only two crystallography distinct fluorine atoms are required to describe this molecule of sulphur hexafluoride, while four are required for the one labelled S(2). (The crystallography distinct atoms are shown in full in the figure, while symmetry related ones are shown in outline only.)

© Copyright 1995-2006.  Birkbeck College, University of London. Author(s): Jeremy Karl Cockcroft