Highly volatile alkaline earth metal fluoroalkoxides.
William D Buchanan1, Marites A Guino-o, Karin Ruhlandt-Senge
1Department of Chemistry, 1-014 Center for Science and Technology, Syracuse University, Syracuse, New York 13244-4100, USA.
Inorganic Chemistry
|July 13, 2010
Summary
Novel alkaline earth metal perfluoro-tert-butoxides (PFTB) were synthesized and characterized. These compounds exhibit low-temperature sublimation, indicating potential for metal organic chemical vapor deposition (MOCVD) applications.
Area of Science:
- Inorganic Chemistry
- Materials Science
Background:
- Alkaline earth metal complexes are crucial in various chemical applications.
- Perfluoro-tert-butoxide ligands offer unique electronic and steric properties.
- Developing novel precursors for advanced material deposition techniques is an ongoing challenge.
Purpose of the Study:
- To synthesize and characterize a new series of alkaline earth metal perfluoro-tert-butoxides.
- To investigate their structural diversity and thermal properties.
- To evaluate their potential as precursors for metal organic chemical vapor deposition (MOCVD).
Main Methods:
- Synthesis via alkane elimination, direct metalation with ammonia activation, and transamination.
- Structural characterization using X-ray crystallography.
- Thermal analysis using thermogravimetric analysis (TGA).
Main Results:
- Successfully synthesized a novel family of alkaline earth metal perfluoro-tert-butoxides with the general formula [Ae(PFTB)2(d)x].
- Compounds exhibit cis or trans conformations in octahedral or pseudo-octahedral environments.
- Thermogravimetric analyses reveal low-temperature sublimation with minimal residue.
Conclusions:
- The synthesized alkaline earth metal perfluoro-tert-butoxides are structurally diverse.
- Their favorable thermal properties, including sublimation, make them promising candidates for MOCVD.
- This research expands the library of potential precursors for thin-film deposition.
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