Period 3 oxides and chlorides

Period 3 oxides and chlorides:

http://www.chemguide.co.uk/inorganic/period3menu.html#top

Aluminium chloride changes structure when melted:

http://www.rod.beavon.clara.net/aluminiu.htm

Tetrahedron of structures:

http://www.meta-synthesis.com/webbook/38_laing/tetrahedra.html