Modeling of Ionization Energy of Elements Using Hartree-Fock Method: An Introduction to Computational Quantum Chemistry for Undergraduate Students

Krishnamohan G P^1, , Thomas Mathew², Simi Saju² and James T. Joseph³

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

²Department of Chemistry, St. Johns College, Anchal, Kollam, India

³Department of Chemistry, Mar Ivanios College (autonomous) Nalanchira, Trivandrum, Kerala, India

Cite this paper:
Krishnamohan G P, Thomas Mathew, Simi Saju and James T. Joseph. Modeling of Ionization Energy of Elements Using Hartree-Fock Method: An Introduction to Computational Quantum Chemistry for Undergraduate Students. World Journal of Chemical Education. 2017; 5(3):112-119. doi: 10.12691/wjce-5-3-6

Abstract

The periodic properties of elements are central to the concept of chemistry and are deeply depending on the electron configuration of atoms. Among the common periodic properties such as atomic radii, electronegativity, electron affinity, the ionization energy of elements gives a clear trend in periodicity. Here, we present a classroom activity, mainly for undergraduate students, to simulate first ionization energy as an important periodic property of elements (up to xenon atom). A set of Hartree-Fock calculations were performed with Gaussian 03 suit of programs and the results have been compared with that of the experimental values. While comparing the experimental and calculated values, we have stressed the role of central-field approximation in the HF theory, important features of Slater type orbitals near the nucleus and the significance of electron correlation in multi-electron systems. Some suggestions for improvement of the results are also discussed.

Keywords:
periodic properties computational chemistry Hartree-Fock ionization energy atomic structure

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