Jahn-Teller effect, theory and examples

Submitted by Adam Johnson / Harvey Mudd College on Thu, 08/06/2020 - 18:44
Description

At a recent SLiThEr workshop, a request was put out for an introduction to the Jahn-Teller effect. I had already prepared several slides showcasing single crystal X-ray data for my class this spring so I put this together with some additional examples from my lab and the literature.  Single crystal XRD data is presented to support the claims.

A cobalt hydroformylation catalyst tribute to Malcolm Green

Submitted by Chip Nataro / Lafayette College on Mon, 07/27/2020 - 20:00
Description

In this paper (Llewellyn, Green and Cowley, Dalton Trans. 2006, 4164-4168) the synthesis and characterization of two cobalt compounds with an N-heterocyclic carbene ligand (IMes) are reported. the first, [Co(CO)3(IMes)Me] was prepared by the reaction of [Co(CO)3(PPh3)Me] with IMes. The second compound, [Co(CO)3(IMes)COMe] is formed by the addition of Co to the first.

Crystal Field Activation Energy Exploration

Submitted by Adam Johnson / Harvey Mudd College on Sat, 06/13/2020 - 19:30
Description

I have long taught CFAE as a topic in my inorganic class, but only over the last 3-5 years has the concept really solidified with me. I think this exercise really does a good job explaining that even a simple theory can have predictive power. I have not seen this analysis in a textbook. Lots of books discuss CFAE and its impact on rate, but taking it to the next step and benchmarking it on real data and ∆o values, I have not seen. Maybe it is because I am not a kineticist and don’t see the “obvious” implications of this.

Gold carbonyl complexes

Submitted by Adam Johnson / Harvey Mudd College on Tue, 06/09/2020 - 15:06
Description

I've been meaning to write an LO on non-classical metal carbonyl complexes for a long time. This paper describes the synthesis and characterization of a gold carbonyl prepared in superacidic media. The LO asks the students to do some relatively straightforward reduced mass calculations to predict the 13C labeled CO stretch from the unlabeled one, but then asks the students to think about /why/ the Au-CO stretch is /higher/ than that of free CO.

MO diagram for square planar methane guided inquiry

Submitted by Adam Johnson / Harvey Mudd College on Tue, 05/19/2020 - 18:16
Description

This guided inquiry activity takes students through the process of constructing an MO diagram for square planar methane. LGOs are constructed using a graphical approach. Students are guided through a process that allows them to use their MO diagram to make a claim about chemical properties.

MO diagram for water guided inquiry

Submitted by Adam Johnson / Harvey Mudd College on Tue, 05/19/2020 - 16:59
Description

This guided inquiry activity takes the students through the whole process of constructing an MO diagram for water in detail. The LGOs are constructed using my graphical approach (linked below) and hybrid orbital formation is discussed. Along the way, students are given hints on what to think about when constructing an MO diagram.

Oscillating Stereocontrol: A Strategy for the Synthesis of Thermoplastic Elastomeric Polypropylene

Submitted by Shirley Lin / United States Naval Academy on Mon, 05/18/2020 - 15:25
Description

This literature discussion focuses upon the Science article by Coates and Waymouth reporting the synthesis of thermoplastic elastomeric polypropylene by an unbridged zirconocene. This article was the basis for the work done for my PhD thesis in the Waymouth group. The LO was written in May 2020 in honor of Bob Waymouth's 60th birthday. See the BITeS post announcing the LO here

How to write a (good) paper

Submitted by Adam Johnson / Harvey Mudd College on Wed, 04/29/2020 - 17:50
Description

This came through my twitter feed today and I thought I would share. I'm linking to McNeil's "Resources" page which has a lot of useful info, but I am specifically talking about the "How to Write a Paper" pdf docuemnt that came from her group taking a few group meetings to discuss what made a good paper. I think this is definitely someting I will keep in mind as I work on my writing this summer!

Ferrocene acylation - The Covid-19 Version

Submitted by Chip Nataro / Lafayette College on Sat, 03/21/2020 - 12:56
Description

This is the classic Chromatography of Ferrocene Derivatives experiment from "Synthesis and Technique in Inorganic Chemistry" 3rd Ed. (1986 pp 157-168) by R. J. Angelici.

setting up an air-sensitive reaction (video)

Submitted by Adam Johnson / Harvey Mudd College on Fri, 03/20/2020 - 20:56
Description

This is a video I made to demonstrate the basics of air-sensitive reaction setup under nitrogen flush. It is the simplest, most basic method for setting up a reaction with air/water sensitive reagents.

The link goes to my channel on YouTube.