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.

A copper "Click" catalyst for the synthesis of 1,2,3-triazoles

Submitted by Chip Nataro / Lafayette College on Wed, 06/10/2020 - 11:40
Description

This paper (Gayen, F.R.; Ali, A.A.; Bora, D.; Roy, S.; Saha, S.; Saikia, L.; Goswamee, R.L. and Saha, B. Dalton Trans2020, 49, 6578) describes the synthesis, characterization and catalytic activity of a copper complex with a ferrocene-containing Schiff base ligand. The article is relatively short but packed with information. However, many of the details that are assumed knowledge in the article make for wonderful questions some of which I hope I have captured.

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.

chromium and molybdenum arene complexes (COVID-19 version)

Submitted by Adam Johnson / Harvey Mudd College on Sat, 03/21/2020 - 19:49
Description

April 2021 update: I am in the process of expanding this laboratory and have now recorded videos, linked below, on youtube. There is a video of general air sensitive reaction setup, the synthesis and isolation of the mesitylene and the N,N-diethylaniline derivatives. I also have better quality data which I will add here as well.

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.

virtual inorganic lab experiments with data

Submitted by Adam Johnson / Harvey Mudd College on Fri, 03/20/2020 - 17:44

This collection includes new and/or updated lab experiments useful for online/distance learning. To be included in this collection, data should be provided for others to use in their new virtual laboratory courses. This collection was prepared as part of my response to the COVID-19 pandemic.

Job's Method - The Covid-19 Version

Submitted by Chip Nataro / Lafayette College on Thu, 03/19/2020 - 23:03
Description

This is the classic Job's Method experiment from "Synthesis and Technique in Inorganic Chemistry" 2nd Ed. (1977 or 1986 pp 108-114) by R. J. Angelici. There are slight changes from the experiment published in the book but they just include running solutions with ethylenediamine mole fractions of 0.67 and 0.75, so details will not be provided. What is provided are a series of pictures and videos showing the experiment being performed. Also included are the raw files of the absorbance spectra in EXCEL.