Spectroscopic and Differential Scanning Calorimetric Studies of the Order–Disorder Phase Transition in Bicyclononanone

✍ Scribed by Ralph M. Paroli; Denis F.R. Gilson; Ian S. Butler

• Publisher: Elsevier Science
• Year: 1998
• Tongue: English
• Weight: 168 KB
• Volume: 136
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1997.7635

✦ Synopsis

The phase transition in bicyclononanone, C 9 H 14 O, has been examined using differential scanning calorimetry, variabletemperature vibrational spectroscopy, and proton spin-lattice relaxation time measurements. The high-temperature phase is disordered and the low-temperature phase either has an orthorhombic crystal with D 2 or C 2 symmetry or is tetragonal with D 2d symmetry. The barrier to rotation in the low-temperature phase between 250 and 300 K is 45.1 kJ mol ؊1 . In the hightemperature phase, two relaxation processes were observed, with activation energies of 11.7 (300-330 K) and 7.7 kJ mol ؊1 (>330 K).