Organic Chemistry |
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Professor Carl C. Wamser |
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Chem 334 - Fall 2003 |
Workshop 2 |
This workshop is intended to familiarize you with the Spartan CD that comes
with your textbook. It has two programs (SpartanBuild and SpartanView)
that allow you to do numerous exercises and problems indicated in your
textbook. The full program has many more capabilities and is available
on the computers in the Chemistry Commons (SB1-221).
1. SpartanBuild - Creating Molecular Structures
Refer to Appendix 3 in your textbook and follow the instructions for creating
propanal.
a) Practice with all of the following motions: rotate, translate, zoom,
and rotate in plane.
b) View the molecule in all of the possible formats under the Model menu.
c) Minimize the energy and measure the bond distances for every C-C and
C-H bond.
Describe and explain any trends you see.
d) Measure bond angles about the sp3 and sp2 carbons. Describe and explain
any trends you see.
e) Measure dihedral angles. Describe and explain any trends you see.
f) Follow the instructions to create malonic acid and trans-1,4-diphenylcyclohexane
as well.
2. SpartanView - Visualizing Molecular Structures and Properties
Quit SpartanBuild, open SpartanView, and open the file for Problem 1-68
(see textbook, p 56).
a) Click on each of the molecules in turn and note the names in the
window titlebar.
b) Determine the magnitude and direction of dipole moments for each
molecule.
c) Determine atomic charges for each atom in each molecule. Why don't
they add to zero in some cases?
d) Click on each molecule in turn and view the potential map (solid)
for each one.
Try the other views (mesh, transparent) as well. What information does
this provide about the molecules?
Close all and open Appendix B.
e) Select ethylene and view the HOMO and LUMO.
f) Select butane and view the animation of conformational changes.
Click one frame at a time.
Rotate the molecule for a Newman-type view of the conformational
changes.
Select Energy and tabulate (graph) the energy changes as the conformation
changes.
3) Spartan - Calculation of Molecular Properties Olympiad
Each of the computers in the Chemistry Commons has MacSpartan or
PCSpartan installed.
a) Open the program and build any isomer of formula C3H6O . Minimize
its energy.
b) Compare results from the group with respect to dipole moments,
atomic charges, and stability.
c) Continue until the group is convinced it has made all possible
isomers.
d) Identify the isomers that deserve gold, silver, and bronze in
as many relevant categories as you can think of (e.g., most positive
carbon).
Try
to determine
what aspects of the structures makes these compounds winners in their
categories.
e) Select any compound and set up a calculation for a potential
surface.
4) Make sure you can do all of this on your own computer
as well, then practice with the rest of Appendix 3.
You can now get the
most benefit
out of the
computer exercises and problems in the chapters (identified with
the CD icons).