Quantum Mechanical Calculations for Diatomic Nitrogen, Dimethyl Peroxide, and O-Xylene
Lindsey Westphal and Holleigh Graminske

Abstract:
    Multiple molecular properties for diatomic nitrogen, dimethly peroxide, and o-xylene were calculated including vibrational energies, electrostatic potentials, dipole moments, partial charges, highest occupied molecular orbitals (HOMO) and lowest unoccupied molecular orbitals (LUMO). Different levels of theory were used, but the best geometry was used for the calculations.
Introduction:
    Molecular orbitals reflect molecular structure and explain some experimental characteristics caused by electron location. Basic molecular structure was determined in the program Avogadro with its solution being input into the program MacMolPlt to optimize the molecular geometry. The program GamessQ was utilized to run quantum mechanical basis sets. Basis sets were used for intense quantum calculations as it is capable of computing molecular bond lengths, electrostatic potentials, vibrations, etc. The molecules were run through one basis set to get general improvement and to decrease the calculation time before being fed into the next basis set in the following order: 3-21G, 6-21G, 6-31G, and DZV. Each subsequent basis set refined the molecular structure with energy minimization being the objective. The program Jmol allowed the visualization of the calculations produced by GamessQ.

Information for these molecules can be found by clicking the following links: diatomic nitrogen, dimethyl peroxide, ortho-xylene

References:
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