With dithiocarbamates

Complexes with dithiocarbamates involve linear S-Au-S coordination but are dimeric and the Au-Au distance of 276 pm compared with 288 pm in the metal and 250 pm in gaseous Au2 is indicative of metal-metal bonding. ... 

Dimeric gold(I) complexes with dithiocarbamate ligands possess a strong propensity to aggregate and form chains with short intermolecular Au Au contacts, they have been known for a long time but new structural characterizations have come into light. Thus compounds of the type... 

An ultra accelerator capable of vulcanising at temperatures as low as 38 °C (100 °F). In mixtures with dithiocarbamate accelerators it is used for room temperature vulcanisation. 

Interesting results were reported with dithiocarbamates derived from diamines. Thus, a series of dinuclear zinc(II), cobalt(II), and nickel(II) dithiocarbamate ditopic macrocyclic receptors containing various spacer groups of different sizes has been reported.412,413,414 Spectroscopic investigations and... 

Metal ions PRE-CD with dithiocarbamate +0.7 to +1.2 glassy carbon 37... 

A number of Se(ll) and Te(Il) complexes with dithiocarbamate (and related) ligands apparently form paramagnetic MS2(C2v) chromophores in solution (150). The electronic spectra of these systems can be treated as p-p spectra, and have been successfully interpreted using the AOM. 

Figure 4.21 Flotation recovery of marmatite as a function of pulp potential with dithiocarbamate as a collector at different pH (DDTC 10 mol/L)...

The anodic scan section of cyclic voltammetry for pyrrhotite electrode, respectively, in pH=7, 8.8, 11, 12.1, 12.7 buffer solution with dithiocarbamate are presented in Fig. 4.28. The cyclic voltammograms curve at pH = 8.8 is also presented in Fig. 4.28. It can be seen that the anodic ciurent peak emerges at about O.IV. As pH increases, the peak moves to the left. This peak may correspond to the formation of disulphide. When the concentration of dithiocarbamate is 10 mol/L, the oxidation of dithiocarbamate forming disulphide is h = 0.22 V, which agrees with the results in Fig. 4.26. When the hydrophobic entity disulphide was formed, the flotation of pyrrhotite could be possible. 

Figure 7.41 is the polarization curves of sphalerite-carbon combination electrode in different collector solution at natural pH. The corrosive electrochemistry parameters are listed in Table 7.8. These results show that xanthate and dithiocarbamate have distinctly different effects on sphalerite. The corrosive potential and current of sphalerite electrode are, respectively, 42 mV and 0.13 pA/cm at natural pH in the absence of collector, -7 mV and 0.01 pA/cm in the presence of xanthate, and 32 mV and 0.12 pA/cm in the presence of dithiocarbamate. The corrosive potential and current decrease sharply with xanthate as a collector, indicating that the electrode surface has been totally covered by the collector film from the electrode reaction. Xanthate has big inhibiting corrosive efficiency and stronger action on sphalerite. However, the corrosive potential and current of sphalerite electrode have small change with dithiocarbamate as a collector, indicating that DDTC exhibits a weak action on sphalerite. 

A series of complexometric extractions were performed to optimize the mobUiza-tion/purging of metallic ions from samples of processing condensate of chromated copper arsenate (CCA). Whereas Cr(VI) and Cu(II) were rapidly mobilized into isobu-tylmethyl ketone-amended SCCO2 after reaction with dithiocarbamate or alkylxan-... 

Crystal structures of [Au2(E E)2]2+ (E = chalcogen donor atom) have been described with dithiocarbamate [265-271], xantate [272], MNT [273-275], dithiopho-sphonate [276], dithiophosphinate [277], dithiophosphate [278, 279] or trithiocarbo-nate [280] ligands. The gold-gold interaction in complexes shown in Figure 2.48 has been analyzed by ab initio Hartree-Fock calculations [281]. 

Nickel(III) complexes with dithiocarbamates are still rare, the best examples being Ni(Et2dtc)3 and Ni(Bu2dtc)2I. Ni(Et2dtc)3 has been prepared by oxidation of Ni(Et2dtc)2 with... 

Nickel(IV) complexes with dithiocarbamates are more stable than the nickel(III) ones. Complexes of formula [Ni(R2dtc)3]X (R = Et, Bu X = Br, I) are generally prepared by halogen oxidation of the parent nickel(II) complexes at room temperature.3227-3229... 

Thioxanthato (alkyl- or aryl-trithiocarbonato) (RSxan) complexes are known for a few metals only. The methods of preparation are mentioned in ref. 1. The ligand field strength does not differ much from that of the xanthates.110 IR spectra give strong carbon-sulfur stretching vibrations in the regions 990-980 and 950-940 cm-1.1 The contribution of the resonance form (98) is low.60 Electrochemical studies show extended redox series, e.g. (99)111 [compare with dithiocarbamates (100)].112... 

Many other sulfur compounds exhibit dimerisation reactions of this type in the presence of metal ions and oxygen. For example, dithiocarbamates are readily oxidised to the disulfides in the presence of copper salts (Fig. 9-13). Very often, attempts to form complexes with dithiocarbamate ligands are complicated by the parallel oxidation process. 

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