These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Mixed amido/imido/guanidinato complexes of niobium: potential precursors for MOCVD of niobium nitride thin films.
    Author: Baunemann A, Bekermann D, Thiede TB, Parala H, Winter M, Gemel C, Fischer RA.
    Journal: Dalton Trans; 2008 Jul 28; (28):3715-22. PubMed ID: 18615218.
    Abstract:
    Novel mixed amido/imido/guanidinato complexes of niobium are reported. The complexes were synthesized by insertion of two equivalents of di-isopropylcarbodiimide (i-Pr-cdi) or bis-cyclohexylcarbodiimide (Cy-cdi) respectively, into the niobium-amido bonds of [Nb(NR(2))(3)(N-t-Bu)] (, R = Me; , R = Et) starting out from [NbCl(3)(N-t-Bu)(py)(2)] and the respective LiNR(2) reagent (py = pyridine). Four representative examples of these mixed ligand amido/imido/guanidinato compounds were synthesized and were characterized by (1)H-NMR, (13)C-NMR, (15)N-NMR, CHN-analysis, mass spectrometry and infra-red spectroscopy. The molecular structures of [Nb(NR(2)){eta(2)-(i-Pr-N)(2)C(NR(2))}(2)(N-t-Bu)] (, R = Me; , R = Et) in the solid state were determined by single-crystal X-ray diffraction studies and are discussed together with the molecular structure of the starting compound [Nb(NMe(2))(3)(N-t-Bu)] (). The thermal properties of the new compounds depend on the substitution at the guanidinato ligand. Complexes of i-Pr-cdi are significantly more volatile than complexes of Cy-cdi as revealed by thermogravimetric analysis. Preliminary experiments using as a single-molecule source for metal-organic chemical vapour deposition (MOCVD) in the absence of ammonia indicate the formation of the stoichiometric, and surprisingly carbon-free, cubic niobium nitride phase.
    [Abstract] [Full Text] [Related] [New Search]