Computational Chemistry Experiments for a General Chemistry Course

TCE

The Chemical Educator

ISSN: 1430-4171 (electronic version)

Table of Contents

Abstract Volume 21 (2016) pp 296-301

Computational Chemistry Experiments for a General Chemistry Course

Michelle M. Ivey*^,†, Nathan H. Robinson^†, Marilyn K. Smith^†,‡, and Jason L. Sonnenberg*^,§

^†Department of Chemistry, Stevenson University, 11200 Ted Herget Way, Owings Mills, MD 21117, mivey@stevenson.edu^‡Department of Chemistry, McDaniel College, 2 College Hill, Westminster, MD 21157; ^§Gaussian Inc., 340 Quinnipiac Street, Building 40, Wallingford CT, 06492, jason@gaussian.com
Received August 18, 2016. Accepted October 5, 2016.

Published: 1 December 2016

Abstract. Computational chemistry is an integral part of the modern undergraduate chemistry curriculum because it can provide a visual approach to understanding structure and how it relates to function. Calculations can be used to understand topics such as molecular shape, chemical reactivity, along with predicting physical and chemical properties. This article describes three activities that were designed for use in General Chemistry Laboratory. In the first experiment, students use molecular modeling to relate geometry to Lewis structures of six simple molecules. This allows them to understand how the presence of lone pairs in Lewis structures affects molecular shape, and to compare the results predicted from classical and quantum mechanical bonding theories. They also display the dipole vector and map the electrostatic potential to better understand polarity. The second experiment is divided into three parts. In the first part, students build an ammonia molecule, and then do an optimization calculation using each of the three levels of theory. In the second part students relate carbon-carbon bond length to total energy for three hydrocarbons. In the final part, students explore carbon monoxide and molecular oxygen acting as ligands binding to iron. In the third experiment, the maximum electrostatic potential is used to predict the pK_a of two acids. These three experiments can be incorporated into a general chemistry course, either as a group or individually, depending upon needs of the department and the needs of the student population.

Key Words: Computers in Chemistry; general chemistry

(*) Corresponding author. (E-mail: mivey@stevenson.edu )

Article in PDF format (162 KB) HTML format

Supporting Materials:

Copies of student handouts (created in Word 2010, and also converted to PDFs) for each experiment are available online. Instructor notes and answer keys for each experiment can be obtained by emailing the corresponding authors. Formatted checkpoint files (*.fch), created using GaussView 5.08 and Gaussian 09W, for each acid in Experiment 3 are also available online. These files can be read by Gaussian, independent of the brand of computer that created them. (6.14 MB)