I use this activity as a "badge," which is self-paced guided skill-building activity that students complete on their own time outside of class. Badges are designed around fundamental chemistry skills that students wouldn’t necessarily acquire from standard course content and lectures. They carry a very small point value (about 2% of the course total per badge) but my students are very motivated by even small amounts of points. I assign points primarily based on completion and effort and also provide brief written feedback for each student. I have my students turn in badges in Moodle, which makes feedback more streamlined.
This is an activity designed to introduce general chemistry students to reading the chemistry literature by familiarizing them with the structure of a published article. The activity first presents an article from the Whitesides group at Harvard about writing a scientific manuscript, along with a video about the peer-review process. There are two parts to the questions in the activity, which are based on a specific article from Nature Communications (doi.org/10.1038/s41467-019-08824-8). Part I is focused on the structure of the article and where to find key pieces of information. Part II encourages students to use general audience summaries in combination with the original article to best understand the science while making sure they get a complete and accurate picture of the reported work.
A student should be able to approach the chemistry literature and determine where to find:
- the authors and their affiliations;
- the main objective of the research;
- the main outcomes of the research;
- why the research is important;
- experimental details;
- supplementary figures and other information.
A student should be able to broadly evaluate the reliability of secondary summaries of scientific articles by comparing them against the key points of the original paper.
This activity is based on a specific article: "Room temperature CO2 reduction to solid carbon species on liquid metals featuring atomically thin ceria interfaces" (Nat. Commun., 2019, 10, 865. doi.org/10.1038/s41467-019-08824-8). However, it's easily adapted to other articles that are more suited to a particular course, and I've used other articles in previous iterations. This article was chosen because the content is at least partly accessible to students in my second semester general chemistry course, who have already had some electrochemistry/redox chemistry, and who have recently learned about kinetics, reaction mechanisms, and catalysis. The topic of liquid metals is new and interesting to the students, because it's not something the'd normally be exposed to, and the application to CO2 sequestration is something they can connect with.
Students completed this activity in small groups, then turned in individual worksheets. Student learning and performance were assessed through 1) in-class group discussion after they had worked on the activity in small groups, and 2) grading the individual worksheets. Participation was most important in the small-group portion.
In general, students really enjoyed this exercise and felt that it was helpful for visualizing metal-organic frameworks (particularly the extended 3D structure). They also generally felt that it was helpful in visualizing the bonding sites of metal vertices, particularly for thinking about how that influences potential reactivity. We used Mercury as a visualization software for this discussion, and the majority of students felt very comfortable using Mercury and looking at cifs on their own after this activity.
The biggest challenge for students seemed to be in relating the 3D structure in the cif to the images and chemicals formulas in the article. They also tended to need some hints about question 5 – to think about what information Mössbauer can provide about oxidation state of the metal, or that you can tell whether or not there are two distinct iron environments. In our class, we do brief units on X-ray crystallography including how to use and interpret cifs, and Mössbauer spectroscopy before this literature discussion. If those topics are not already addressed in a particular class it might be helpful to add them in or directly address those topics for the students as an introduction to the literature discussion.
This literature discussion explores the physical structures, electronic structures, and spectroscopic characterization of several porphyrin-based metal-organic frameworks through discussion of “Iron and Porphyrin Metal−Organic Frameworks: Insight into Structural Diversity, Stability, and Porosity,” Fateeva et al. Cryst. Growth Des. 2015, 15, 1819-1826, http://dx.doi.org/doi:10.1021/cg501855k. The activity gives students experience visualizing and interpreting MOF structures, and gives students exposure to some of the methods used to characterize MOFs.
Students will be able to:
- Interpret and describe the bonding and structural characteristics of MOFs
- Apply knowledge of ligand field strength to electronic structure of MOFs
- Analyze X-ray crystallographic data to gain information about structural characteristics of MOFs
- Interpret Mössbauer spectra to gain information about electronic structure of MOFs
This literature discussion was designed for use in an advanced (upper-level) inorganic chemistry course, but could be used in a foundational inorganic course if students have already been introduced to d-splitting diagrams and are given some coverage of Mössbauer spectroscopy and X-ray crystallography. When covering MOFs in class, students frequently expressed that visualizing and understanding the bonding sites and extended 3D structures was very challenging. So, this literature discussion was developed specifically to address that. Students completed this activity in small groups. It is very helpful to advise students ahead of time to bring laptops (or instructor should have some available) and to have the cifs from the paper downloaded and ready to go. We used Mercury as a visualization software for this activity. This activity can easily be completed in one class period. It is also helpful if students have been provided with the article ahead of time and encouraged to look it over – otherwise the most time-consuming part of this activity was allowing time for students to examine the MOF structure images in the paper before being able to discuss and answer the questions with their groups.
Note on visualization of MOFs using Mercury: To answer the discussion questions, we used the ‘stick’ or the ‘ball and stick’ style. We also used the default packing scheme (0.4x0.4x0.4) and the 1x1x1 packing scheme. The packing scheme can be changed by selecting Packing/Slicing… in the Calculate menu. I also had students view the 3x3x3 packing scheme – while this is not necessary to answer the discussion questions, it was interesting for students to be able to visualize the extended structure of the MOFs.
This is a collection of LOs that I used to teach a junior-senior seminar course on organometallics during Fall 2018 at Harvey Mudd College. There were a total of 9 students in the course. The Junior student (there was only one this year) was taking 2nd semester organic concurrently and had not takein inorganic (as is typical).
During our first fellows workshop, the first cohort of VIPEr fellows pulled together learning objects that they've used and liked or want to try the next time they teach their inorganic courses.