Submitted by Robert Q. Topper / Cooper Union on Tue, 06/25/2013 - 01:55
My Notes
Categories
Prerequisites
General Chemistry
Organic Chemistry
Physical Chemistry: Quantum Mechanics
Physical Chemistry: Thermodynamics
Corequisites
No Corequisites
Course Level
Upper Division/Graduate
Topics Covered
Bonding models: Discrete molecules
Chemical literature
Computer modeling
Electronic structure
Molecular structure
Periodic trends
Physical methods / analytical techniques
Physical properties
Subdiscipline
Electrochemistry
Main Group Chemistry
Solid State and Materials Chemistry
Description

In this project students are asked to reproduce published calculations of molecular orbital energies of a series of derivatized fullerenes and correlate them with published reduction and oxidation potentials obtained from cyclic voltammetry. The particular subset of the derivatives to be studied are chosen by the student and this choice is part of the learning activity. The students then carry out additional calculations using other theoretical models to see whether they improve the correlation between computed and experimental properties. Interpretation of the trends and suggestions for additional work are discussed in a formal report. 

Attachment Size
ComputRedoxTrendsCyclicVolt2013.docx 23.39 KB
ComputRedoxTrendsCyclicVolt2013.pdf 242.23 KB
Learning Goals

After completing this project, students will be able to

  • Summarize the use of cyclic voltammetry to measure redox potentials;
  • Use computer software to build and visualize molecular models of derivatives of buckminsterfullerene;
  • Carry out density functional theory and semiempirical calculations of buckminsterfullerenes;
  • Discuss how derivatization affects the energies of the frontier orbitals;
  • Implement different theoretical models and correctly choose the one which best correlates with the experimental data;
  • Discuss which computational method is likely to be most useful in the prediction of redox potentials from first principles; and
  • Write a formal report describing their findings.
Equipment needs

Modern computer workstation with 6+ GB RAM; molecular structure building and visualization software; quantum mechanics software. Spartan 8 has all of the capabilities required for this project.

 

Related activities
Cyclic voltammetry
Computational Inorganic Chemistry: An Introduction
Basics of Computational Chemistry
Implementation Notes

The models are built and the calculations are carried out at our institution using Spartan 10, but Gaussian, GAMESS, Q-Chem, NW-Chem or other programs with similar capabilities could be used instead. 

Time Required
Students are asked to complete this as an independent project, although the work could be done as a group in one or two laboratory periods if a computer classroom is available.
Web Resources
J. Am. Chem. Soc. 1994, 116, 1359-1363.
Alternative Experiment #4: Cyclic Voltammetry
J. Phys. Chem. C 2012, 116, 6349-6356.
Tutorial on Ab Initio Redox Potential Calculations
Evaluation
Evaluation Methods

Students write a formal report which is evaluated with respect to whether each learning goal is achieved.

Evaluation Results

Earlier versions of this project have been assigned to approximately 30 students in three senior-level inorganic chemistry courses over a six year period, with substantial revisions made each time. Students were generally able to reproduce the literature results successfully and to gauge which method is expected to be most reliable for first-principles calculations of redox potentials. There was some variability in students’ choice of fullerenes which appropriately span the range of interest. Some students were able to make fairly sophisticated suggestions for future work. 

Creative Commons License
Attribution, Share Alike CC BY-SA
Kim / Chestnut Hill College

This is a great introduction to electrochemistry. I actually started using this in my physical chemistry course.

Sat, 11/18/2017 - 13:27 Permalink
Robert Q. Topper / Cooper Union

Thanks! Yes, I've used it in both kinds of courses too. 

 

Wed, 02/27/2019 - 14:29 Permalink