Coordination compounds described

Organometallic compounds commonly exhibit high reactivities compared to the coordination compounds described previously. Their visible and/or ultraviolet absorption spectra are so complicated that the assignments are often difficult. Theoretical calculations, their reactivities, and spectroscopic data suggest the characteristic natures of chem-... 

In relation to the synthetic direction of the present monograph, we would like especially to mention that the theoretical approach of Lewis is the basis of preparative techniques in the synthesis of coordination compounds described later (Chap. 3) interaction of the ligands with metal salts or carbonyls (Sec. 3.3.1) is described by Schemes (1.1) and (1.2), ligand exchange (Sec. 3.3.2.1) by Schemes (1.3) and (1.6), metal exchange (Sec. 3.2.2) by Schemes (1.4) and (1.7) ... 

Photochemical behaviour of coordination compounds described in previous chapters results mainly from electronic interactions between the central metal atom or ion and ligands in the hrst coordination sphere. An increased size of molecular systems to clusters and nanosized crystals expands the possibility of photoinduced electron transfer between the discrete electronic states to excitation within bands. Furthermore, interactions of nanoparticles with molecules yield unique materials, combining structural versatility of molecular species with collective properties of solids. 

Pauling and John C. Slater applied the valence bond theory to coordination compounds, describing the bonding in terms of overlap of an orbital of the ligand containing a lone pair of electrons with a vacant hybridised orbital on the central metal ion. This model gave a satisfactory explanation of both the geometry and... 

Be familiar with the coordination numbers, geometries, and ligands of complex ions name and write formulas for coordination compounds describe the types of constitutional and stereoisomerism they exhibit ( 22.2) (SPs 22.2, 22.3) (EPs 22.18-22.39)... 

MOMEC is a force field for describing transition metal coordination compounds. It was originally parameterized to use four valence terms, but not an electrostatic term. The metal-ligand interactions consist of a bond-stretch term only. The coordination sphere is maintained by nonbond interactions between ligands. MOMEC generally works reasonably well for octahedrally coordinated compounds. 

The chemistry of Cr(III) in aqueous solution is coordination chemistry (see Coordination compounds). It is dominated by the formation of kineticaHy inert, octahedral complexes. The bonding can be described by Ss]] hybridization, and HteraHy thousands of complexes have been prepared. The kinetic inertness results from the electronic configuration of the Cr ion (41). This type of orbital charge distribution makes ligand displacement and... 

Despite the weak basicity of isoxazoles, complexes of the parent methyl and phenyl derivatives with numerous metal ions such as copper, zinc, cobalt, etc. have been described (79AHC(25) 147). Many transition metal cations form complexes with Imidazoles the coordination number is four to six (70AHC(12)103). The chemistry of pyrazole complexes has been especially well studied and coordination compounds are known with thlazoles and 1,2,4-triazoles. Tetrazole anions also form good ligands for heavy metals (77AHC(21)323). 

Several different types of isomers arise in transition-metal coordination compounds, and these are described below. 

Example provides more practice in working with the names of coordination compounds. Our Chemical Milestones Box describes the detective work that led to the birth of coordination chemistry. 

Throughout this chapter we will use in the different Schemes the abbreviation [Zr] = CpjZrCl- thus [Zr]-H = [Cp2Zr(H)Cl]n (1) and [Zr]-R = Cp2Zr(R)Cl. Most of the compounds described in this chapter have metal centers with 16 electrons, and it is important to emphasize that any coordinatively unsaturated zirconocene (IV) complexes can potentially exist as dimeric, oligomeric, or polymeric aggregates. 

Wilkinson s treatise on applications of coordination compounds includes a chapter that describes the use of formazan/tetrazolium systems... 

Structural aspects were discussed, but not heavily, in the first edition. The complexity of new compounds (and macromolecules) now being investigated has driven many of the technological advances in X-ray crystallographic data collection and structure solution over the last two decades. Small-molecule (m.w. < 1,000 g mol-1) structure determinations are now routinely carried out, and Co complexes constitute a significant proportion of these. Indeed, the incorporation of crystal structures in most papers reporting new synthetic coordination chemistry is now a standard feature much more so than at the time of CCC(1987) (Figure 1). Inevitably, most of the new compounds described herein have been the subject of crystal structure determinations, rather... 

The divalent Co(salen) complex (69a) is one of the most versatile and well-studied Co coordination compounds. It has a long and well-documented history and we shall not restate this here. Recent applications of (69a) as both a synthetic oxygen carrier and as a catalyst for organic transformations are described in Sections 6.1.3.1.2 and 6.1.4.1 respectively. Isotropic shifts in the HNMR spectrum of low-spin Co(salphn) (69b) were investigated in deuterated chloroform, DMF, DMSO, and pyridine.319 Solvent-dependent isotropic shifts indicate that the single unpaired electron, delocalized over the tetradentate 7r-electron system in CHCI3, is an intrinsic property of the planar four-coordinate complex. The high-spin/low-spin equilibrium of the... 

A review28 describes compounds of the Pt-group metals including halide, oxide, sulfide, coordination compounds, organometallic compounds, and metal cluster compounds. 

The chief aim of this Formula Index, like that of other formula indexes, is to help in locating specific compounds, or even groups of compounds, that might not be easily found in the Subject Index, or in the case of compounds in tables or of many complex coordination compounds, not to be found at all in the Subject Index. All specific compounds, or in some cases ions, with definite formulas (or even a few less definite) are entered in this index, whether entered specifically in the Subject Index or not. As in the latter index, boldface type is used for formulas of compounds or ions whose preparations are described in detail, in at least one of the references cited. 

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