Difluoroamine
Here are the results of the computations on HNF2. In general the
larger
the basis set the more accurate the calculation, although some basis
sets are more well suited to certain types of calculations than others.
This is demonstrated by comparing the calculated bond lengths,
dipole moments, and bond angles with the literature.
|
3-21G
|
6-31G |
DZV |
Literature |
| N-F |
1.421487 |
1.402891 |
1.403660 |
1.3528 |
| N-H |
1.013186 |
1.007172 |
1.009190 |
1.024 |
| F-N-F |
102.73
|
103.46 |
103.47 |
103.18 |
| F-N-H |
101.29 |
102.48 |
102.83 |
|
Table 5 - Difluoroamine bond lengths and angles, Angstroms and degrees.
Here
we have mixed results from our basis sets. The larger DZV came
closer to the measured value for the N-H bond length but the smaller
6-31G set came closer to the N-F bond length. DZV came closest to
the measure value of the F-N-F bond angle.
|
|
|
|
Figure 4 - Difluoroamine with
bond lengths and angles. |
|
|
|
|
|
Figure 5 - Difluoroamine with
HOMO. |
|
Displayed are HNF2 highest occupied molecular orbitals.
Note that the generated orbitals are rather distorted from what we
would draw from VSEPR.
Below is shown applets
depicting the motion associated with calculated vibrational
frequencies. For comparison, click this link for the
NIST Webbook page for HNF2.
|
|
|
|
Figure 6 - Motion associated
with 1081.5 cm^-1. |
|
The most intense vibrational frequeny is
at 1081.5cm^-1 and corresponds to the rotational motion of the hydrogen
atom about the nitrogen center. This frequency does not
correspond with the listed NIST values, however.
|
|
|
|
Figure 7 - Motion associated
with 1369.3 cm^-1. |
|
The other intense vibrational frequeny
is at 1369.3cm^-1 and also corresponds to bending motion of the
hydrogen about the nitrogen center, and is reasonably close to the NIST
value of 1307 cm^-1.
Below is selected UV vis
data that was calculated.
| 3-21G |
6-31G |
DZV |
Literature |
| 120692.80
|
117494.64
|
90058.67
|
|
| 98912.15 |
128023.46
|
116370.91 |
|
|
|
123011.30
|
|
|
|
127602.39
|
|
Table 6 - Selected UV vis data, cm^-1.
The frequencies listed were chosen because they had considerably
greater intensity than the others.
Based on template by A. Herráez as modified by J. Gutow
Using directory C:/Users/Compaq/Desktop/Wes and Natasha/HNF2 page
adding JmolPopIn.js
...jmolApplet0
...adding HNF2_bond_lengths_and_angles.png
...copying
C:/Users/Compaq/Desktop/Wes and Natasha/HNF2_AM1_6-31G.log
to
C:/Users/Compaq/Desktop/Wes and Natasha/HNF2 page/HNF2_AM1_6-31G.log
...adding HNF2_bond_lengths_and_angles.spt
...jmolApplet1
...adding HNF2_HOMO.png
...adding HNF2_HOMO.spt
...jmolApplet2
...adding HNF2_1081_5cm_-1.png
...copying
C:/Users/Compaq/Desktop/Wes and Natasha/HNF2_AM1_DZV_Hessian.log
to
...compressing large data file to
C:/Users/Compaq/Desktop/Wes and Natasha/HNF2 page/HNF2_AM1_DZV_Hessian.log.gz
C:/Users/Compaq/Desktop/Wes and Natasha/HNF2 page/HNF2_AM1_DZV_Hessian.log.gz
...adding HNF2_1081_5cm_-1.spt
...jmolApplet3
...adding HNF2_1369_3cm_-1.png
...adding HNF2_1369_3cm_-1.spt