Thorium amidates function as single-source molecular precursors for thorium dioxide

Straub, Mark D.; Ouellette, Erik T.; Boreen, Michael A.; Branson, Jacob A.; Ditter, Alex; Kilcoyne, A. David; Lohrey, Trevor D.; Marcus, Matthew A.; Paley, Maria; Ramirez, José; Shuh, David K.; Minasian, Stefan G.; Arnold, John

doi:10.1039/d1cc00867f

DOE OSTI · 1779749

Thorium amidates function as single-source molecular precursors for thorium dioxide

Straub, Mark D.·Ouellette, Erik T.·Boreen, Michael A.·Branson, Jacob A.·Ditter, Alex·Kilcoyne, A. David·Lohrey, Trevor D.·Marcus, Matthew A.·Paley, Maria·Ramirez, José·Shuh, David K.·Minasian, Stefan G.·Arnold, John

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Abstract

Here, we report the synthesis of four homoleptic thorium(IV) amidate complexes as single-source molecular precursors for thorium dioxide. Each can be sublimed at atmospheric pressure, with the substituents on the amidate ligands significantly impacting their volatility and thermal stability. These complexes decompose via alkene elimination to give ThO 2 without need for a secondary oxygen source. ThO 2 samples formed from pyrolysis of C-alkyl amidates were found to have higher purity and crystallinity than ThO 2 samples formed from C-aryl amidates.

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Straub, Mark D., Ouellette, Erik T., Boreen, Michael A., Branson, Jacob A., Ditter, Alex, Kilcoyne, A. David, Lohrey, Trevor D., Marcus, Matthew A., Paley, Maria, Ramirez, José, Shuh, David K., Minasian, Stefan G., Arnold, John. 2021-04-20. Thorium amidates function as single-source molecular precursors for thorium dioxide. https://doi.org/10.1039/d1cc00867f

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