Studebaker D B, Neumayer D A, Hinds B J, Stern C L, Marks T J
Department of Chemistry, Materials Research Center, and Science and Technology Center for Superconductivity, Northwestern University, Evanston, Illinois 60208-3113, USA.
Inorg Chem. 2000 Jul 24;39(15):3148-57. doi: 10.1021/ic991161a.
The synthesis, characterization, and incorporation in volatile metal-organic chemical vapor deposition (MOCVD) precursors of a new class of linked beta-ketoiminate-polyether-beta-ketoiminate ligands is presented. These ligands are designed to encapsulate alkaline-earth cations having low charges and large ionic radii. Barium complexes having the general formula Ba[(RCOCHC(R')N)2(R")] (R = tert-butyl or CF3; R' = tert-butyl, methyl, or CF3; R" = -(CH2CH2O)4CH2CH2- or -(CH2CH2O)5CH2CH2)-) were prepared and characterized by 1H and 13C NMR spectroscopy, elemental analysis, and mass spectrometry. Single-crystal X-ray diffraction analysis of 2,2,5,25,28,28-hexamethyl-9,12,15,18,21-pentaoxa-4,25-diene-6,24- diimino-3,27-pentacosadionatobarium(II) reveals a monomeric, nine-coordinate, tricapped trigonal prismatic coordination geometry. Single-crystal X-ray structural analysis of 1,1,1,24,24,24-hexafluoro-4,21-ditrifluoromethyl-8,11,14,17- tetraoxa-3,21-diene-5,20-diimino-2,23-tetracosadionatobarium(II).2DMSO reveals a monomeric, ten-coordinate, distorted tetracapped trigonal prismatic coordination geometry. Volatility data are presented for these barium complexes, demonstrating viability as MOCVD precursors. In addition, it is demonstrated that thin epitaxial films of BaTiO3 can be grown on (001) MgO by low-pressure MOCVD techniques using one of these barium complexes and Ti(dipivaloylmethanate)2(isopropoxide)2 as precursors.
本文介绍了一类新型的连接β-酮亚胺-聚醚-β-酮亚胺配体的合成、表征及其在挥发性金属有机化学气相沉积（MOCVD）前驱体中的应用。这些配体旨在包裹电荷低、离子半径大的碱土金属阳离子。制备了通式为Ba[(RCOCHC(R')N)2(R")]（R = 叔丁基或CF3；R' = 叔丁基、甲基或CF3；R" = -(CH2CH2O)4CH2CH2-或-(CH2CH2O)5CH2CH2-）的钡配合物，并通过1H和13C NMR光谱、元素分析和质谱对其进行了表征。对2,2,5,25,28,28-六甲基-9,12,15,18,21-五氧杂-4,25-二烯-6,24-二亚氨基-3,27-二十五碳二酮钡（II）的单晶X射线衍射分析表明其具有单体、九配位、三帽三角棱柱配位几何结构。对1,1,1,24,24,24-六氟-4,21-二（三氟甲基）-8,11,14,17-四氧杂-3,21-二烯-5,20-二亚氨基-2,23-二十四碳二酮钡（II）.2DMSO的单晶X射线结构分析表明其具有单体、十配位、扭曲的四帽三角棱柱配位几何结构。给出了这些钡配合物的挥发性数据，证明了其作为MOCVD前驱体的可行性。此外，还证明了使用这些钡配合物之一和Ti（二（新戊酰基甲烷）2（异丙醇）2）作为前驱体，通过低压MOCVD技术可以在（001）MgO上生长BaTiO3外延薄膜。
