My Notes
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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
- plan diagrams
- static 3D models (generated by CrystalMaker)
- CrystalMaker files on a computer (I have a license for my laptop)
- online sites like ChemTube3D
- ICE Solid State Model Kits
I believe that it’s important to guide students as they explore 3D extended structures. Since there is no lab directly associated with my class, all of our visualization activities are done in a standard lecture room during one or more 50-minute class periods. While students can work with the free demo version of CrystalMaker on a computer, most students don’t bring their computers to class. However, most students have smartphones and tablets.
This activity describes how to generate DAE files (3D interchange file format). These files can be opened on student devices so that students can individually work with 3D models of extended solid state structures.
| Attachment | Size |
|---|---|
| COLLADA INSTRUCTIONS_0.docx | 233.51 KB |
| CsCl_1.dae | 2.09 MB |
| halite1.dae | 4.12 MB |
| halite2.dae | 1.73 MB |
A student will be able to use alternate representations of extended solids to better visualize solid state structures.
I recommend that students download Studio Viewer and the Canvas (LMS) App before class. I also recommend that they practice getting files from Canvas to Studio Viewer before they come to class. (In the future, I will ask them to move all of these files to Studio Viewer prior to class.)
To streamline the transfer process, I make a single page that contains all of the DAE files so students only need to go to a single page on the LMS.
I’ve attached a few DAE files here. You can find many more with the associated LO, “A model for every student: Visualizing solid state structures”.
Evaluation
I used the SALG (Student Assessment of Learning Gains) to see how much different aspects of the course help their learning. In 2015 (model kits only) and 2016 (model kits and Studio Viewer), I asked about the gains they made in understanding solid state structures. In 2016, I asked how much the model kits and Studio Viewer helped their learning.
On the end of semester SALG in 2016, I asked students about the solid state model kits and Studio Viewer. “HOW MUCH did each of the following aspects of the class HELP YOUR LEARNING?”
| Solid State Model Kits | Studio Viewer | |
| No help | 2% | 2% |
| A little help | 9% | 9% |
| Moderate help | 2% | 9% |
| Much help | 11% | 22% |
| Great help | 69% | 58% |
| Not Applicable | 2% | 2% |
The students responded more favorably to the solid state model kits, but 80% of students thought that both the model kits and Studio Viewer provided much or great help.
I also asked, "As a result of your work in this class, what GAINS DID YOU MAKE in your UNDERSTANDING of each of the following?" Here are student responses for extended (solids) structure
| Spring 2016 | Studio Spring 2015 | |
| No gains | 2% | - |
| A little gain | 7% | 10% |
| Moderate gain | 7% | 6% |
| Good gain | 36% | 41% |
| Great gain | 33% | 29% |
| Not Applicable | - | 2% |
As you can see, there are not great differences between the year I used Studio Viewer (Spring 2016) and the year I used only model kits.
I gave students the option of using it to help them complete an exam question and ~25% of my students used it on the exam. (Students who used the viewer were more likely to get the problem correct because using the viewer removed the ambiguity of where atoms in the unit cell could be found.)
If you are looking for an open-source alternative to CrystalMaker, the Chimera program appears to do many of the same things and allows you to export DAE files.
https://www.cgl.ucsf.edu/chimera/
The .dae viewer I was using no longer works for me. One of my students found a great, online option to view and manipulate .dae files: https://threejs.org/editor/
It's platform independent. Not only can you rotate and zoom in on the structure, but you can also selectively move atoms and view multiple structures at once.