never is going to exist, a fictional state.

3.
There is an old adage with regards to computers: “Garbage in = Garbage out”. That is, if you
start with a bad geometry (garbage), then the program may converge to a bad geometry
(garbage). For
instance,
you
might
have
bad angles
or
bond
distances
that
make
convergence difficult for your molecule.
This geometry did not converge to a ‘correct ‘geometry
and the job failed. The atoms are too close to each other and the chain is too strained. On the
other
hand,
starting
with
this
geometry
the calculation converged
just
fine. The molecule is
‘stretched out’ in a chain that is more realistic for larger hydrocarbons.
For this pro
blem you are trying to find some ‘bad’ initial geometries that do not converge to the
proper structures. Use PM3. Show a bad initial geometry that did not converge (the calculation
failed, or the final geometry is not correct). Also show a good initial geometry that did converge
toa correct final geometry. Do this for 2 different molecules. That is, provide 1 bad initial
geometry and 1 good initial geometry
for
molecule
1,
and 1
bad initial
geometry and
1
good
initial
geometry
for molecule 2.
Molecule 1: Bad
Molecule 1: Good

Molecule 2: Bad
Molecule 2: Good

4.For this problem you are to compare different methods for hydrogenation reactions. Calculate
the reaction
energies
for the

#### You've reached the end of your free preview.

Want to read all 6 pages?

- Summer '20
- Chemistry, Electron, Quantum Chemistry, Molecule