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.
The guided reading questions may be graded using the answer key.
These questions have not yet been assigned to students.
Guided reading and in-class discussion questions for "High-Spin Square-Planar Co(II) and Fe(II) Complexes and Reasons for Their Electronic Structure."
1. Bring together ligand field theory and symmetry.
Students should be able to identify symmetry of novel molecules in the literature.
Students should be able to explain d-orbital ordering in a coordination complex using ligand field theory.
Students should be able to identify donor/acceptor properties of previously unseen ligands.
Students should be able to apply your knowledge of electronic transitions to the primary literature.
Students should be able to become more familiar with 4-coordinate geometries.
Students should be able to predict magnetic moments of high-spin and low-spin square-planar complexes.
Students should be able to identify properties of ligands that favor formation of the highly unusual high-spin square planar complexes.
2. Students should comfortable with reading and understanding primary literature.
You do not have to assign all of the guided reading questions at once. You may consider assigning questions as they pertain to where you are in your inorganic chemistry class.
The classroom discussion (participation, answers, etc) may be assessed by the instructor, or alternatively, these questions could be given to students to turn in.
None yet available. Please leave yours in the comments!
This literature discussion aims to have students in an advanced inorganic chemistry course interpret reaction schemes and electronic spectra, relate chemical formulae to molecular structure, and gain an understanding of how inorganic synthesis is planned and executed. Students should gain an understanding of how counterions and crown ethers affect structure. Question 7 may be expanded to ask students to why pi-donor ability affects ligand field splitting, or as an introfuction to this topic.
An associated 1FLO based on this paper is linked in the related content.
This LO is intended for an advanced inorganic chemistry course. Students should read the communication before class with questions above as guidance. A classroom discussion should insue, in which students gain an insight into inorganic synthesis, and recognize how minor differences between compounds, such as counterions, have significant effects on electronic structure.
Evaluate students' comprehension based on verbal in-class answers and ensuing discussion.
None yet available.
This 1FLO asks students to interpret an electronic spectrum of 5 NiX42- anions. Students will determine the relative ligand field strength, (re)familiarize themselves with terms such as "redshift" and "blueshift", and consider possible metal complex geometries.
Students (re)familiarize themselves with relationship between wavelength (λ) and wavenumber (cm-1).
Students recall 4-coordinate geometries.
Students define the terms “redshift” and “blueshift.”
Students analyze data to construct a partial spectrochemical series.
None
This activity could be used as either a guided introduction to the spectrochemical series, or as an in-class activity to review after introduction. If used as an introduction, question 4 may need modification.
Performance and participation in the discussion will be assessed
None collected yet. Evaluation data will be added in the future.
This paper in Science reports the synthesis of decamethyldizincocene, a stable compound of Zn(I) with a zinc-zinc bond. In the original LO, the title compound and the starting material, bis(pentamethylcyclopentadienyl)zinc, offer a nice link to metallocene chemistry, electron counting, and different modes of binding of cyclopentadienyl rings as well as more advanced discussions of MO diagrams. More fundamental discussion could focus on the question of what constitutes the evidence for a chemical bond, in this case, the existence of a zinc-zinc bond. In this updated LO, these topics are still covered, however additional topics, such as point group idenitifaction, details regarding the reaction mechanism, electronic structure, and searching the literature using SciFinder are covered. Additionally, electron counting is divided into both the covalent and ionic models.
Students should become more confident reading the primary literature
Students should be able to apply existing knowledge to interpret research results.
Students should be able to apply electron counting formalisms to organometallic compounds.
Students should be able to use 1H NMR spectroscopy data to rationalize structure.
Students can rationalize bond distances based on periodic trends in atomic radii
Students use SciFinder to put this work into a larger context.
Students identify redox reactions based on oxidation changes.
Students identify molecular point groups based upon structures.
Students should be able to connect d electron count to observed colors of compounds.
Students are asked to read the paper and the accompanying Perspectives article before class as well as answer the discussion questions. The questions serve as a useful starting point for class discussion.
Do these students identify the same colors as the students without visual impairments?
Are their lab results correct?
Students were able to accurately describe colors.
I have had some students in class have a hard time identifying colors (flame tests, solution color, acid-base indicators, etc.) because of a visual impairment. There are many cell-phone apps that are helpful in aiding these students. "Pixel Picker" allows the students to load a picture from a device (cell phone, ipad). This is helpful because students are now dealing with a "frozen" image. Moving the cross-hair to different parts of the picture changes the R-G-B values. The "Color Blind Pal" app uses a more qualitative approach. It names the color in the cross-hair using various color scales. There are also different options for different types of color blindness.
Both of these apps are free and availble in the App Store.
A student should be able to correctly identify an unknown metal by the color of its flame.
A student should be able to correctly identify the endpoint in a titration by the indicator's color change.
A student should be able to correctly describe the physical properties (color) of a sample.
A student should be able to correctly predict the visible absorbance spectrum of a solution based on correctly identifying the color of the solution.
Have the students with visual impairments practice using the app ahead of time to better prepare them to use the app for the first time in class/lab. Students would also need to understand the additive nature of light colors. For example, high R and G values will appear yellow/orange. I would give these students a 1-page handout for their lab notebook with the addative color wheel and various colored circles labeled with their names and RGB values so that students could practice and reference in the lab.
Our lab safety contract actually has students indicate whether they are color blind. This is a good time to introduce these students to the apps.
This exercise takes longer than a 50 minute class period, so we get as far as we can in one class and the students complete the exercise as homework. Students write their answers to the questions directly on the handout. Tables are provided for recording numerical results, but because of some (simple) required mathematical manipulations, it is easier if students set up a spreadsheet and record their numerical results there. The handouts with their answers and printed copies of their spreadsheet are collected in the next class.
In Exercise 1, the vibrational spectrum of formaldehyde is calcuated by three different methods. Because the vibrational modes come out in a different order, energy-wise, in one of the methods, students have trouble keeping track of which vibration is which. Each mode is labeled with the correct symmetry label, which should help them. Plus, they can click on each mode and visualize it.
Exercise 2 involves calcuating delta H for an "isodesmic" reaction: one in which the total number and type of bonds is the same in reactants and products. This helps cancel any systematic errors in the calculations. If this is one of the first time that students have worked in "hartrees," it is helpful to explain that unit to them. Students compare semi-empirical calculations with HF and DFT, and in this example, the HF and DFT calculations give much more accurate results.
Exercise 3 is about calculating UV-Vis spectra, but more importantly it walks students through drawing more complicated molecules. The CIS/ZINDO approach is used for the UV-Vis calcuation, which may not be highly accurate, but is very fast, so students get rapid results that they can compare.
In Exercise 4, students calculate NMR spectra for three different molecules. It teaches students about chemical shifts, but it does not cover coupling constants. If students are experienced with NMR, the averaging of proton resonances (such as the three protons in a methyl group) has become second nature to them. This exercise forces them to think about how those resonances are averaged.
This is the fifth in a series of exercises used to teach computational chemistry. It has been adapted, with permission, from a Shodor CCCE exercise (http://www.computationalscience.org/ccce). It uses the WebMO interface for drawing structures and visualizing results. WebMO is a free web-based interface to computational chemistry packages (www.webmo.net).
In this exercise, students perform infrared, thermochemistry, UV-Vis, and NMR calculations. They compare the results from different methods and basis sets to experimental values.
The exercise provides detailed instructions, but does assume that students are familiar with WebMO and can build molecules and set up calculations.
Students will be able to:
Students need access to a computer, the internet, and WebMO (with Mopac and Gaussian).
I use this as an in-class exercise. Students bring their own laptops and access our institution's installation of WebMO through wifi.
A portion of their grade (20%) is dedicated to literature discussions (4-6 over the course of the semester). The grading rubric involves 3 possible ratings for each question/answer: “excellent”, “acceptable”, or “needs work”.
Concepts covered during literature discussions will be included among exam materials.
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This Guided Literature Discussion was assigned as a course project, and is the result of work originated by students Christopher Lasterand Patrick Wilson. It is based on the article “Deca-Arylsamarocene: An Unusually Inert Sm(II) Sandwich Complex” by Niels J. C. van Velzen and Sjoerd Harder in Organometallics 2018, 37, 2263−2271. It includes a Reading Guide that will direct students to specific sections of the paper that were emphasized in the discussion. This article presents a study of the reactivity of bulky CpAr-Et/iPr2 Sm complexes that is contrasted to the more well-known Cp*2Sm.
After reading and discussing this article, a student should be able to…
- Be more familiar with the chemistry of sandwich samarocene complexes.
- Understand how bulky ligands affect structure and reactivity in a sandwich complex.
- Apply the CBC method to identify ligand functions and metal valence number/ligand bond number.
- Understand how XRD bond distances can help determine a ligand charge.
I am planning on assigning this LO as a graded in-class group discussion. Students will be given a copy of the article, reading guide, and discussion questions one week in advance. On the day of the discussion, students will be assigned in groups of 2-3. They will then have one lecture period to answer the questions in writing as a group. [This article is among the free-access ACS Editors’ Choice.]
Concepts covered during literature discussions will be included among exam materials.
N/A
This Guided Literature Discussion was assigned as a course project, and is the result of work originated by students Jana Forster and Kristofer Reiser. It is based on the article “Mechanism of the Platinum(II)-Catalyzed Hydroamination of 4-Pentenylamines” by Christopher F. Bender, Timothy J. Brown, and Ross A. Widenhoefer in Organometallics 2016 35 (2), 113-125. It includes a Reading Guide that will direct students to specific sections of the paper that were emphasized in the discussion. This article presents a mechanistic study of hydroamination reactions catalyzed by a late transition metal complex.
After reading and discussing this article, a student should be able to…
- Apply the CBC electron-counting method.
- Understand how 31P {1H} NMR can help differentiate intermediates.
- Use information provided by Eyring plots.
- Understand how a catalyst resting state and turnover-limiting step can be identified.
- Understand the role of kinetics in mechanistic investigations.
- Appreciate how proposed reaction mechanisms can be evaluated.
I am planning on assigning this LO as a graded in-class group discussion. Students will be given a copy of the article, reading guide, and discussion questions one week in advance. On the day of the discussion, students will be assigned in groups of 2-3. They will then have one lecture period to answer the questions in writing as a group. A portion of their grade (20%) is dedicated to literature discussions (4-6 over the course of the semester). The grading rubric involves 3 possible ratings for each question/answer: “excellent”, “acceptable”, or “needs work”. [This article is among the free-access ACS Editors’ Choice.]
This is a basic introduction to Enemark-Feltham that can be used in conjunction with any literature that has Iron nitrosyls in it. I made this as a follow up to the work that came ouf of the 2018 VIPEr workshop in UM-Dearborn.
A student will be able to detemine the Enemark-Feltham label for a simple iron nitrosyl
A student will be able to describe bonding differences between NO+, NO, and NO- ligands.
I haven't used this yet, but It can be a quick lecture module or online module to help students understand Enemark-Feltham before analyzing a paper on iron nitrosyls.
