A new type of catalyst for the syndiospecific polymerization of styrene, Cp*Ti(N(CH2CH2O)3) (3), was prepared by either the reaction of triethanolamine with Cp*TiCl3 in the presence of triethylamine or the reaction of (N(CH2CH2O)3)TiCl with LiCp*. The former reaction route is more efficient in terms of yield and easy accessibility of a titanium starting compound. The X-ray analysis reveals that 3 exists in a monomeric form in the solid state and the Ti atom adopts essentially an η5 bonding posture with regard to the Cp* ring and a tetradentate bonding mode with regard to the triethanolateamine ligand via a transannular interaction from the bridgehead N atom to Ti. The compound 3, which is stable to air and heat and soluble in hydrocarbon solvents, shows very efficient catalytic activity for the syndiospecific polymerization of styrene in the presence of modified methylaluminoxane (MMAO) as cocatalyst.

A novel C s -symmetric yttrocene complex, ansa-Me 2 Si(η 3 -Flu)(η 5 -Cp′)YCl 2 Li(OEt 2 ) 2 (3; Flu ) C 13 H 8 , fluorenyl; Cp′ ) C 5 Me 4 ), has been prepared via a salt metathesis reaction from anhydrous YCl 3 and the dilithium salt of the ligand ansa-Me 2 Si(FluH)(Cp′H). Treatment of 3 with NaN(SiMe 3 ) 2 gave the corresponding bis(trimethylsilyl)amide derivative ansa-Me 2 -Si(Flu)(η 5 -Cp′)YN(SiMe 3 ) 2 (4). The X-ray structure of 3 reveals unusual η 3 -fluorenyl coordination to the Y 3+ ion. In 4, the Y-Flu bonding being partially slipped toward η 3 from η 5 , π-dative bonding nature in the Y-N bond and a direct interaction of the Y atom with one methyl group of the N(SiMe 3 ) 2 fragment are present. Both compounds constitute the first examples of structurally characterized fluorenyl ansa-yttrocenes. The neutral compound 4 is active for the polymerization of methyl methacrylate (MMA) in toluene, affording isorich poly(MMA)s.

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The phase formation and electrical properties of (Bi,La) 4 Ti 3 O 12 (BLT) thin film and V-, Sm-doped BLT thin films prepared by the chemical solution deposition method on Pt/TiO 2 /SiO 2 /Si substrates have been investigated. It was observed that the microstructure and electrical properties of BLT thin films dramatically varied with V-and Sm-doping. The crystallinity and grain size of BLT thin films were definitely increased by V-and Sm-doping into BLT films, which resulted in the enhancement of remanent polarization in doped BLT films. The remanent polarization (Pr) of Sm-doped BLT films annealed for 3 min by an RTA system was about 9 µC/cm 2 . The V-and Sm-doped BLT films also exhibited good fatigue characteristics under bipolar stressing to 10 10 cycles.

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