Rob Scarrow's Web Pages about Crystal Structures

Graphical introduction to unit cells in crystals

This page uses animated gif files to teach about the translational symmetry found in crystals, and to explain the meaning of "unit cell" and how to determine the elemental composition of the unit cell.

Structures of selected ionic and metallic solids (updated; now uses Jmol rather than Chime)

This page compares the structures of various solids that have cubic point groups, to emphasize the similarities and differences between various structures of metallic and ionic structures. Uses a Jmol applet; you should see a bunch of small buttons with asterisks; if not something is wrong with Jmol - perhaps try another browser (works with Safari and Firefox on Mac - 2/2012).

Structures of molecular solids (requires a pdb viewer such as Rasmol)

It is common for chemists and biologists to show pictures of molecules in ball and stick or wireframe views based on structures obtained from X-ray crystallography. It is less common for them to show pictures of how the molecules pack together to form a semi-infinite lattice of repeating unit cells. Clicking on the title above will allow you to compare views of a coordination complex showing a single molecule with another view showing roughly 50 molecules packed together in the semi-infinite lattice.

Structures of elements (Web Elements site)

I recommend the WebElements.com site. It has, over the years, become very ad intensive, but still has lots of useful information. You can browse and compare the structures and properties of the different elements. Here is a page I use with quick links to show my Gen Chem class.

Relevant to experiments 17-19 from the Chem 101 lab manual, here are several different 3-D structures of the [CoCl2(en)2]+ cation. These may be viewed with using the Chime plug-in (for more info click here) or the stand-alone program Rasmol (see below).
Here are a few structure other files maintained locally (may be viewed with Chime or Rasmol (see below)):
Recommended www links: