The goal of this activity is to have students calculate the empirical formula of a compound given the contents of a unit cell.
A repeating building block, or unit cell, is used to represent extended structures since shifting a unit cell along its edges by the length of the edge will exactly replicate the extended structure.
The page has JSmol structures for unic cells including cubic, body centered cubic, and face centered cubic unit cells as well as for CsCl, Ni3Al, Cu2O, NaCl, CaF2, ZnS, diamond, Li3Bi, NaTl, NiAl and ReO3. The advanced page also has triclinic, monoclinic, hexagonal, orthorhombic, and tetragonal cells with all possible centering.
Although I’m a solid state chemist, I still find it difficult to teach the visualization of solid state structures. I’m interested in any tool that helps my students visualize solids. My experience is that the more representations students can master, the more likely they are to find one that helps them understand solid state structures.
I’ve used many tools. These include
We do not cover extended solids (solid state materials) in our general chemistry program. With the exception of students who have taken a course in materials science, Inorganic Chemistry I is the first time our students have encountered solid state structure. Although they have built some visualization skills by working with molecules and symmetry, they do not have robust 3D visualization abilities and have trouble using the language of solid state chemistry (unit cells, packing, filling holes, coordination number, etc…) in the context of structure.
This is a short worksheet that guides students through simple metal lattices (SCP, CCP, HCP) and how filling holes in these lattices results in ionic lattices (NaCl, CsCl, fluorite, etc.).
The worksheet was used as an in-class activity after students had read about the material in the text. This activity is probably suitable for first-year students, though I used it with juniors/seniors.
The colors of transition metal compounds are highly variable. Aqueous solutions of nickel are green, of copper are blue, and of vanadium can range from yellow to blue to green to violet. What is the origin of these colors? A simple geometrical model known as crystal field theory can be used to differentiate the 5 d orbitals in energy. When an electron in a low-lying orbital interacts with visible light, the electron can be promoted to a higher-lying orbital with the absorption of a photon. Our brains perceive this as color.
This list includes a number of LOs to help in teaching nanomaterials subjects; however, it is not exhaustive.
Updated June 2018.
ColourLex (colourlex.com) is an amazing website that mixes chemistry and art. The creators of this website have extensively catalogued paintings and the pigments that were used to create them. The pigments range from artificial to natural and organic to inorganic. You can search for the specific combination that you want to see.
The Cambridge Crystallographic Data Centre (CCDC) provides many free programs that can be used to view and manipulate crystal structures. Additionally, they have made a subset of the Cambridge Structural Database (CSD) available for teaching purposes and many educational activities have been created to go along with this teaching subset (see link below). This teaching subset can be freely viewed through the WebCSD interface or can be used in the freely-available Mercury program. (Mercury is avaliable for Mac, Windows, and Linux systems.)
This is a learning object focused on analyzing a specific figure from a research article that show XPS and CV data on Ni(OH)2/NiOOH thin films that have incorporated Fe.