Geometry Results
The geometry of N2 was calculated using several basis sets. Of the basis sets used, Double Zeta Valence (DZV) was chosen as the most optimal geometry configuration since those calculations resulted in the lowest energy, which correlates to the most accurate representation of the actual molecule. Below is a comparison of the bond lengths and calculated energies calculated by other basis sets and literature values is shown.
From Table 1, one can see that the DZV optimization resulted in a bond length that had the smallest difference from the literature value; however the DZV value is not within the error of the literature value. To gain a more accurate value, a basis set with higher computations should be used. |
Vibrational1 At the DZV theory level, the vibrational frequency of N2 was calculated as 2590.35cm-1 and literature values place the vibrational frequency of N2 to be 2359cm-1 . To see an animation of molecular vibrational states, click here. |
Potential Energy of Bond Stretching Below is a graph showing the potential energy of bond stretching for a N2 molecules at different basis sets. It is easily seen that the higher the basis set, the better the calculated bond length. The red line shows that the DZV calculations resulted in the lowest energy value, thus meaning it is the most accurate basis set to use when determining the potential energy of bond length. |