Record Details
Determination of barriers to internal rotation from low temperature heat capacity data
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Determination of barriers to internal rotation from low temperature heat capacity data |
| Names |
Simpson, Kenneth Owen
(creator) Beynon, Eugene T. (advisor) |
| Date Issued | 1966-09-02 (iso8601) |
| Note | Graduation date: 1967 |
| Abstract | A method by which barrier heights in potential functions hindering internal rotation in organic molecules can be obtained solely from thermal data for the solid phase is studied. The observed heat capacities are analyzed in terms of contributions from the lattice vibrations, the intramolecular vibrations, the expansion of the lattice, and the internal rotation. Five compounds are treated. These are mesitylene, toluene, benzenethiol, methanethiol, and trifluoromethanethiol, Calculations show that the barrier values are 540, 340, 280, 1650, and 1630 cal/mole for the respective molecules. It is shown that the potential barriers are in accord with barriers derived from gas phase entropy calculations and that the calculated and experimental heat capacities agree for the most part well within the expected limits. The precision of the low barriers is better than those determined from gas phase entropy calculations, while the high barrier values have about the same precision as gas phase entropy values. |
| Genre | Thesis/Dissertation |
| Topic | Molecular rotation |
| Identifier | http://hdl.handle.net/1957/47307 |
