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Updated: Oct 31, 2025
Spark Plasma Sintering Apparatus Used for the Formation of Strontium Titanate Bicrystals
Published on: February 9, 2017
Synthesis and Crystal Structures of New Strontium Complexes with Aminoalkoxy and β-Diketonato Ligands
Chanwoo Park1,2, Jeong Min Hwang1, Yongmin Go1
1Thin Film Materials Research Center, Korea Research Institute of Chemical Technology, 141 Gajeong-ro, Yuseong-gu, Daejeon 34114, Republic of Korea.
Abstract:
New heteroleptic strontium complexes were synthesized using substitution reaction of bis(trimethylsilyl)amide of Sr(btsa)2·2DME with aminoalkoxide and β-diketonate ligands. The complexes [Sr(bdmp)(btsa)]2·2THF (1), [Sr(bdeamp)(btsa)]2 (2), [Sr(dadamb)(btsa)]2 (3), [Sr(bdmp)(hfac)]3 (4), [Sr(bdeamp)(hfac)]3 (5), [Sr(dadamb)(hfac)]3 (6), and [Sr3(dadamb)4(tmhd)2] (7) were prepared and characterized by means of various analysis techniques such as Fourier transform infrared, NMR, thermogravimetric analysis, and elemental analysis. Complexes 1-3 were further structurally confirmed by single-crystal X-ray crystallography, and they displayed dimeric structures in which strontium atoms were connected by alkoxide oxygen atoms of the μ2 type. Compound 1 has a trigonal prismatic structure, whereas 2 and 3 have a distorted square pyramidal structure. In complexes 5-7, trimeric structures were obtained with strontium atoms connected by μ3-O bonds of alkoxide oxygen atoms and μ2-O bonds of alkoxide and β-diketonate oxygen atoms. The crystal structures of 5, 6, and 7 showed distorted capped octahedral geometry, while 7 (middle Sr atom) displayed a distorted trigonal prism geometry. Complexes 5-7 displayed ∼70% mass loss in the temperature range from 25 to 315 °C.
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