Isostructural complexes

The exchange of zirconium in isostructural complexes leads to a new family of asymmetric metallocenes (Fig. 1) bearing a 2-methyl substituent and varied substituents in positions 5, 6, and 7 of the indenyl moiety. After borate activation all catalysts show an unexpected high and constant activity toward the polymerization of propylene and lead to significantly increased molecular weight products compared to the zirconocene species [9-11],... 

The first heavier alkali metal phosphide species to be structurally characterized were the sodium and potassium complexes [M P(mes) (SiFBu2) (THF)2]2 (M = Na, K) (67). These isostructural complexes adopt an eight-membered (MPSiF)2 ring motif in which each alkali... 

The formation of complexes with the [NTc(/u-0)2TcN] central structural unit has parallels in molybdenum chemistry, where isostructural complexes such as [ MoO(S2CNEt2) 2(M 0)2] are well established. In the MoO system, the differences for the 0x0 ligand compared to the nitrido ligand are again obvious, since the Mo sites about 0.73 A above the basal plane of the square pyramid, compared to 0.65 A in the technetium case. ... 

Further examples of a cyclic heterometallic potassium amide, obtained from KBu, MgBu2 and tmpH in CgH, or PhMe, are the isostructural complexes [(tmp)i2K6-Mg6(C6H5)6] (Figure 2.8) and [(tmp)i2K6Mg6(C6H4CH3)6] comprised of 24-membered N22K6Mg6 macrocycles that play host to six mono-deprotonated arene molecules... 

Crystal structures of the isostructural complexes [ZnfOH LJ (LH = phenoxyacetic acid or 4-chlorophenoxyacetic acid) have been reported, and the metal has been shown to be in a distorted octahedral Oe environment (108). 

The evidence for the monomeric nature of CpLnX2S3 ] is obtained from the crystal structure [126,127] of isostructural complexes Er and Yb. The Yb complex has a distorted octahedral geometry of the type mer-trans (i.e.) trans chlorines and mer THF ligands. The... 

The cations Fe and Al " are both considered hard acids by Pearson (3. Thus, it is not surprising that a plot comparing stabilities of the isostructural complexes and minerals gives a strong correlation. The oxygen-donor species, in particular, plot nearly on a straight line. The almost exact linearity of the OH... 

The structures of bpy complexes have been probed by a remarkable variety of spectroscopic techniques, partly due to the availability of a wide range of isostructural complexes in which the electronic configu-... 

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