Bond angles at each level of theory studied are listed below in
Table 2
and an interactive model of the molecule with bond lengths displayed is
shown in
Figure 2.
Table 2: Calculated and experimentally determined bond angles of Cl2O2 at different levels of theory and basis sets using the RHF SCF.
Theory
|
Cl-O-O Bond Angle
|
Cl-O-O-Cl Bond Angle
|
PM3
|
110.7 °
|
107.3 ° |
AM1
|
110.7 ° |
107.3 ° |
6-21G
|
115.6 ° |
88.0 ° |
6-31G
|
107.9 ° |
96.3 ° |
DZV
|
109.8 ° |
93.9 ° |
Experimental2
|
110.07 ° |
81.03 ° |
Bond lengths and angles are were not reported for the UHF SCF type
because at every level of theory and basis set, the atoms of the
molecule were "blown apart" (
Figure 3). For the levels of theory
and basis sets that used the RHF type SCF, the semi-empirical AM1 method
produced the bond lengths closest to the experimental values. However,
the dihedral bond angle from the AM1 calculations was the furthest from
experimental values. At the
ab initio level of theory, the DZV
basis set provided the bond lengths and angles closest to the reported
experimental values. Since the DZV optimization provided geometries that
were closest to the
experimental values, these were used to determine several
characteristics of the Cl
2O
2 molecule including the HOMO, LUMO, partial atomic charges, and the electrostatic potential.