Bromine
Bromine is a diatomic molecule with an atomic number of 35 on the
periodic table. This section depicts the geometric optimization of
Bromine (Br
2)
Table 1: Computer method used with the resulting
atomic orbitals and molecular orbitals generated by that method.
Additionally the bond length generated by the subsequent methods.
Method
|
Atomic Orbitals used
|
Molecular Orbitals Generated
|
Bond Length (pm)
|
PM3
|
7
|
8
|
229
|
3-21G
|
35
|
46
|
244
|
6-31G
|
35
|
58
|
241
|
DZV
|
35
|
48
|
243
|
Figure 1: Graph of bond length vs energy for the
ab
inito basis sets. Zoomed in image is of the best geometry
set from 6-21G.
Figure 2: Molecular orbital diagram for bromine (Br
2)
with respective molecular orbital cartoons. The anti bonding pi
orbital is the highest occupied molecular orbital and the anti
bonding sigma orbital is the lowest unoccupied molecular orbital.
A better depiction of the HOMO and LUMO molecular orbitals for Br
2
can be observed below. If the molecular orbital is lower in energy
than the atomic orbital it is a bonding orbital and if the
molecular orbital energy is higher than the atomic orbital it is
an anti bonding orbital.
|
Jmol0 will appear here.
|
|
CLICK IMAGE TO ACTIVATE 3D
Bond Length of Bromine from PM3 geometry optimization. |
The geometry optimizations for PM3, 3-21G, 6-21G, and DZV are
shown below. Bond angles are not shown due to the molecule being
180 degrees.
Image to the right depicts the geometry optimization for PM3
with bond length. PM3 provided the closest bond length to the
theoretical. This was due to bromine being used for the
optimization parameters. That caused the calculated bond length
to have a less than 1% error with the theoretical value of 0.228
nm2.
|
Jmol1 will
appear here.
|
|
CLICK IMAGE TO ACTIVATE 3D
Bond length of bromine with 3-21G geometry optimization. |
Geometry optimization from ab inito theory 3-21G. 3-21G
had to be done instead of 6-31G because it was not optimized for
bromine.
|
Jmol2 will appear here.
|
|
CLICK IMAGE TO ACTIVATE 3D
Bond Length of Bromine from DZV geometry optimization. |
Geometry optimization from ab inito theory from DZV
geometry optimization.
|
Jmol3 will
appear here.
|
|
CLICK IMAGE TO ACTIVATE 3D
Bond Length of Bromine from 6-31G geometry optimization. |
Geometry optimization from ab inito theory from 6-31G
geometry optimization.This proved to be the best when compared
to the theoretical bond length.
|
Jmol4
will appear here.
|
|
CLICK IMAGE TO ACTIVATE 3D
Geometry optimized bromine showing HOMO p orbitals in best
geometry optimized basis set 6-31G. |
Molecular orbital 35: p orbitals for the HOMO molecular
orbitals.
HOMO=Highest Occupied Molecular Orbital
|
Jmol5
will appear here.
|
|
CLICK IMAGE TO ACTIVATE 3D
Geometry optimized bromine showing LUMO p orbitals in best
geometry optimized basis set 6-31G.
|
Molecular orbital 35: p orbitals for the LUMO molecular
orbitals.
LUMO=Lowest Unoccupied Molecular Orbital
Based on a template by A.
Herráez and J. Gutow
Using directory /Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE
adding support.js
...jmolApplet0
...adding bromine_OP_PM3.png
copying and unzipping jsmol.zip directory into /Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE
...copying
file:/Users/gressa71/Desktop/P chem Quantum calc lab/GAMESS calc/Bromine_PM3_OP.log
to
/Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE/Bromine_PM3_OP.log
...adding bromine_OP_PM3.spt
...jmolApplet1
...adding bromine_OP_3-21G.png
copying and unzipping jsmol.zip directory into /Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE
...copying
file:/Users/gressa71/Desktop/P chem Quantum calc lab/GAMESS calc/Bromine_3-21G_OP.log
to
...compressing large data file to
/Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE/Bromine_3-21G_OP.log.gz
/Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE/Bromine_3-21G_OP.log.gz
...adding bromine_OP_3-21G.spt
...jmolApplet2
...adding bromine_OP_DZV.png
copying and unzipping jsmol.zip directory into /Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE
...copying
file:/Users/gressa71/Desktop/P chem Quantum calc lab/GAMESS calc/Bromine_DZV_OP.log
to
...compressing large data file to
/Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE/Bromine_DZV_OP.log.gz
/Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE/Bromine_DZV_OP.log.gz
...adding bromine_OP_DZV.spt
...jmolApplet3
...adding bromine_OP_6-31G.png
copying and unzipping jsmol.zip directory into /Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE
...copying
file:/Users/gressa71/Desktop/P chem Quantum calc lab/GAMESS calc/Bromine_6-31G_OP.log
to
...compressing large data file to
/Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE/Bromine_6-31G_OP.log.gz
/Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE/Bromine_6-31G_OP.log.gz
...adding bromine_OP_6-31G.spt
...jmolApplet4
...adding bromine_OP_6-31G_HOMO.png
copying and unzipping jsmol.zip directory into /Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE
...adding bromine_OP_6-31G_HOMO.spt
...jmolApplet5
...adding bromine_OP_6-31G_LUMO.png
copying and unzipping jsmol.zip directory into /Users/gressa71/Desktop/Website files/BROMINE_WEBPAGE
...adding bromine_OP_6-31G_LUMO.spt