Exploring Potential Energy Surface with Mathematica: An Algorithmic Demonstration of Minimum Energy Path, Stationary Points and Transition State

Krishnamohan G. P.^1, , Omar H.², Sreeja T. D.³ and Roy K. B.⁴

¹Department of Science and Humanities, Mar Baselios College of Engineering and Technology (autonomous), Nalanchira, Trivandrum, Kerala 695015, India

²Department of Chemistry, TKM Arts and Science College, Kollam 691005, India

³Department of Chemistry, Sree Krishna College, Guruvayur, Kerala 680102, India

⁴Department of Chemistry, Sree Neelakanta Government Sanskrit College, Pattambi, Palakkad, Kerala 679306, India

Cite this paper

Krishnamohan G. P., Omar H., Sreeja T. D. and Roy K. B.. Exploring Potential Energy Surface with Mathematica: An Algorithmic Demonstration of Minimum Energy Path, Stationary Points and Transition State. World Journal of Chemical Education. 2022; 10(4):124-130. doi: 10.12691/WJCE-10-4-1

Abstract

The reaction profile (energy profile) is a widely used conceptual tool in chemical kinetics to represent the progress of a chemical reaction. Quantitatively, a reaction profile can be viewed as a minimum energy path (MEP) on the potential energy surface (PES), which connects the reactants and products through one or more transition states or intermediates. In this article, we used Mathematica program to demonstrate a generic method for finding reaction profile on a Müller-Brown PES by applying steepest descent algorithm. The properties of the MEP and stationary points were discussed in detail. The general characteristics of the transition state (TS), and imaginary mode were illustrated with a vibrational analysis of hydrogen exchange reaction, H₂+H → H+H₂.

Keywords

minimum energy path, potential energy surface, transition state, stationary state, imaginary mode

Copyright

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