Transition metal ions table

Racah parameters B and C for the given transition metal ion (Table 46) ... 

The outer configurations of the transition metals in Table 1-1 imply, and detailed spectroscopic investigations confirm, that the 3d orbitals lie at higher energies than the 45 orbitals. On the other hand, the configurations of the ions listed, in... 

Table 1-2. The electronic configurations of the transition-metal ions in the divalent and triva-lent states.

Table 9-4. Hard and soft transition-metal ions and ligands.

Bond length differences between HS and LS isomers have been determined for a number of iron(II), iron(III) and cobalt(II) complexes on the basis of multiple temperature X-ray diffraction structure studies [6]. The available results have been collected in Table 17. Average values for the bond length changes characteristic for a particular transition-metal ion have been extracted from these data and are obtained as AR 0.17 A for iron(II) complexes, AR 0.13 A for iron(III) complexes, and AR = 0.06 A for cobalt(II) complexes. These values may be compared with the differences of ionic radii between the HS and LS forms of iron(II), iron(III) and cobalt(II) which were estimated some time ago [184] as 0.16, 0.095, and 0.085 A, respectively. 

Table II. Comparison of the Reactions of Transition Metal Ions with n-Butane at a Relative Kinetic Energy of 0.5eVa...

Throughout this book a major stress is on catalysis in organisms. Catalysis is confined to non-metals and metal ions of attacking power, either as Lewis acids or in oxidation/reduction and this excludes the simplest ions such as Na+, K+ and Ca2+ (and Cl- among anions). The transition metal ions and zinc are the most available powerful catalysts. The metals in a transition series are known to have selective binding properties, exchange rates and oxidation/reduction states, which can be put to use in catalysis in quite different ways (Table 2.13). It is noticeable that especially the complexes of metal elements... 

The thermodynamic functions (AH, AS, AG(298 K)) of hydrogen peroxide reactions with transition metal ions in aqueous solutions are presented in Table 10.1. We see that AG(298K) has negative values for reactions of hydroxyl radical generation with Cu1+, Cr2+, and Fe2+ ions and for reactions of hydroperoxyl radical generation with Ce4+, Co3+, and Mn3+. 

The values of the rate constants for the reactions of transition metal ions with hydrogen peroxide in an aqueous solution are presented in Table 10.2. 

Peroxyl radicals with a strong oxidative effect along with ROOH are continuously generated in oxidized organic compounds. They rapidly react with ion-reducing agents such as transition metal cations. Hydroxyl radicals react with transition metal ions in an aqueous solution extremely rapidly. Alkyl radicals are oxidized by transition metal ions in the higher valence state. The rate constants of these reactions are collected in Table 10.5. 

Dioxygen oxidizes transition metal ions in the lower valence state generating the hydroxyperoxyl radicals or superoxide ions [155,156]. The thermodynamic characteristics of these reactions are presented in Table 10.6. It is seen that all cited reactions are endothermic, except for the reaction of the cuprous ion with 02. The reaction of the ferrous ion with dioxygen has a sufficiently low enthalpy (28 kJ mol 3). 

The kinetic parameters characterizing the oxidation of transition metal ions by dioxygen are collected in Table 10.8. 

Tables 1.2-1.6 list some of the important geometries assumed by metal ions in biological systems. Common geometries adopted by transition metal ions that will...

Experimental data for solvent exchange on octahedral second- and third-row transition metal ions are limited to the Ru2+/3+, Rh3+ and Ir3+ and to water and acetonitrile solvents (Table VIII (3,125-129)). 

Replacing several solvent molecules on di- and trivalent transition metal ions by non-leaving ligands can have dramatic effects on the solvent exchange rates of the remaining solvent molecule(s) (Tables X, XI, XII and XIII (70,71,83,86-88,92,95,96,146-166) (115,119-121,167-181) (125, 128,129,167,168,181-193)). For example replacing three MeCN solvent... 

Square-planar stereochemistry is mostly confined to the d8 transition metal ions. The most investigated solvent exchange reactions are those on Pd2+ and Pt2+ metal centers and the mechanistic picture is well established (Table XIV (194-203)). The vast majority of solvent exchange reactions on square-planar complexes undergo an a-activated mechanism. This is most probably a consequence of the coordinatively unsaturated four-coordinate 16 outer-shell electron complex achieving noble gas... 

Laser ablation of compounds of almost all elements in the periodic table will produce the bare ion M+. Laser ablation and other methods of producing bare metal ions have been discussed in Section II.C.5. The bare metal ion has a coordination number of 0 and for most elements these ions will aggressively seek molecules able to share or donate electrons. Thus most bare transition metal ions will increase their coordination number by reacting with any donor, this even includes the inert gas atoms such as Xe (96). 

Laser ablation of many metallic compounds will produce not only the bare metal ion M+ but also ions such as [MX]+, where X = O, S, Cl. The early bare transition metals ions react vigorously with background water in the mass spectrometers and the [MO]+ ion is always present when metals such as Ti are ablated. The [MX]+ ions can undergo several types of reaction and three types will be considered here substitution, addition, and polymerization reactions. Table II gives examples of the reactions of [MX]+ and [ML]+ ions. 

Table 5.1 Electron distribution in some transition-metal ions (1s, 2s, 2p, 3s and 3p shells are complete in all cases)...

---