Chapter 30. The Rotational Isomerism of F3CSiMe2SiMe2CF3: Do Three Conformers Exist in the Liquid State?
- Prof. Norbert Auner2,
- Prof. Johann Weis3
Published Online: 28 APR 2008
DOI: 10.1002/9783527619917.ch30
Copyright © 2000 WILEY-VCH Verlag GmbH
Book Title
Organosilicon Chemistry IV: From Molecules to Materials
Additional Information
How to Cite
Zink, R. and Hassler, K. (2008) The Rotational Isomerism of F3CSiMe2SiMe2CF3: Do Three Conformers Exist in the Liquid State?, in Organosilicon Chemistry IV: From Molecules to Materials (eds N. Auner and J. Weis), Wiley-VCH Verlag GmbH, Weinheim, Germany. doi: 10.1002/9783527619917.ch30
Editor Information
- 2
Inst. für Anorganische Chemie, der Universität Frankfurt, Marie-Curie-Strasse 11, D-60439 Frankfurt am Main, Germany, Phone: 0 69/7 98-29180, -29591, Fax: 069/798-29188
- 3
Wacker-Chemie GmbH, Geschäftsbereich S, Werk Burghausen, Johannes-Hess-Strasse 24, D-84489 Burghausen, Germany
Publication History
- Published Online: 28 APR 2008
- Published Print: 17 JAN 2000
ISBN Information
Print ISBN: 9783527298549
Online ISBN: 9783527619917
- Summary
- Chapter
- References
Keywords:
- bis(trifluoromethyl)disilane;
- rotational isomerism;
- Ortho conformer;
- raman spectroscopy;
- ab initio calculations
Summary
Ab initio calculations at the MP2/6–31G* level of theory predict the existence of three enantiorneric pairs of nonequivalent conformers on the potential energy surface of the highly interesting compound F3CSiMe2SiMe2CF3. In agreement with theory the Raman bands at 360 cm-1, 369 cm-1 and 380 cm-1 are assigned to the gauche, ortho and anti conformer, respectively. The relative intensities of these bands vary with temperature, and energy differences between the individual rotamers have been determined from variable temperature Raman spectra as Hgauche-Hanti = 2.65 kJ mol-1, Hortho-Hanti = 2.64 kJ mol-1 and Hgauche-Hortho = 0 kJ mol-1.