Cadmium solid state structure

The reaction of dabco (l,4-diazobicyclo[2.2.2]octane) with Me2Cd yields a 1 1 adduct 197, which adopts a linear polymeric structure (Figure 34).255 The cadmium atom is coordinated by two dabco units and two methyl carbon atoms giving rise to a distorted tetrahedral environment. Finally, the organocadmium adduct 198 (Figure 35) has been isolated from the reaction of Me2Cd with Cd[(SeP-/-Pr2)2N]2.256 The solid-state structure consists of dimeric units where each methylcadmium unit is coordinated to three selenium atoms. The geometry about the cadmium center is tetrahedral with a Cd-C distance of 2.16 A, which is comparable to that observed in other cadmium alkyl complexes. 

R. D. Ernst, T. J. Marks, and J. A. Ibers, Metal-Metal Bond Cleavage Reactions. The Crystallization and Solid State Structural Characterization of Cadmium Tetracarbony-liron, CdFe(CO)4, J. Am. Chem. Soc. 99, 2090-2098 (1977). 

Interest has also continued in the synthesis and solid-state structural characterisation of organophosphido derivatives of main group elements including aluminium,indium,zinc and cadmium,and lead. ... 

Solid State Structures of Cadmium Complexes with Relevance for Biological Systems... 

Another interesting case in crystal engineering is the one of interpenetrated cyano-bridged diamondoid networks. Zinc(II) easily adopts a tetrahedral geometry, so the solid-state structure of Zn(CN)2 is quite predictable tetrahedral zinc ions are connected by cyano groups generating a diamond-like net, with double interpenetration (Schemel). The cadmium derivative. 

Studies of the thermodynamics of formation of complexes of zinc with 2,2 -bipyridine in the presence of halide and thiocyanate ions in DMF has been carried out.205 The zinc complexes of 2,2 -bipyridine with A-(benzenesulfonyl)glycine and A-(toluene- -sulfonyl)glycine were synthesized and infrared data implied a structural analogy with the cadmium complexes. This suggests that the zinc promotes sulfonamide nitrogen deprotonation in the amino acid ligands in the solid state.206... 

The first complex exhibiting 7r-coordination of a Cp ligand to a Cd(ll) center in the solid state, namely, [Cp2Cd-tmeda] 196, has been recently isolated and structurally characterized (Figure 33).254 Both Cp rings interact with the cadmium center in an -fashion with Cd-C distances ranging from 2.34 to 2.74A. 

The solid-state electrochemical formation of bilayer electrode structures of different hexacyanoferrates was studied, and a theoretical model was proposed for cyclic voltammetric behavior of the transformation of PB into cadmium hexacyanoferrates [411]. 

In contrast, the number of known structures of homoleptic, monomeric two-coordinate amides of cadmium is currently limited to just one example. The structure of the compound [Cd N(SiMe3)2 2] has been determined by electron diffraction and the data showed that it has a linear NCdN skeleton with a Cd—N bond length of 2.03(2) A. It is clear, however, that several other homoleptic cadmium amides (known and others as yet not synthesized) can be predicted to have monomeric structures in the solid state. For example Cd NMR studies of amides such as [Cd N(SiMe3)2 2] or [Cd N(SiMe2Ph)2 2] indicate that they are... 

Salts of [W(CN)s]4 are dodecahedral both in solution and in the solid state with the exception of the cadmium salt which is believed to have the square antiprismatic structure in both phases.255 ESR and vibrational spectra suggest that the Wv ion [W(CN)8]3 has DM symmetry in solution.262 However, evidence for both the dodecahedral and square antiprismatic ground state for this ion has also been reported.263... 

Cadmium is a member of Group 12 (Zn, Cd, Hg) of the Periodic Table, having a filled d shell of electrons 4valence state of +2. In rare instances the +1 oxidation state may be produced in the form of dimeric Cd2+2 species [59458-73-0], eg, as dark red melts of Cd° dissolved in molten cadmium halides or as diamagnetic yellow solids such as (Cd2)2+ (AlCl [79110-87-5] (2). The Cd + species is unstable in water or other donor solvents, immediately disproportionating to Cd2+ and Cd. In general, cadmium compounds exhibit properties similar to the corresponding zinc compounds. Compounds and properties are listed in Table 1. Cadmium(TT) [22537 48-0] tends to favor tetrahedral coordination in its compounds, particularly in solution as complexes, eg, tetraamminecadmium(II) [18373-05-2], Cd(NH3)2+4. However, solid-state cadmium-containing oxide or halide materials frequently exhibit octahedral coordination at the Cd2+ ion, eg, the rock-salt structure found for CdO. 

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