Bridging chlorides

PtCl2, and platiaum tetrachloride [37773-49-2]. Platiaum dichloride exists in an a- and P-form, the latter containing a Pt core and edge-bridging chlorides. Platinum trichloride [25909-39-1], PtCl, contains Pt(II) and Pt(IV) centers. Other haHdes include two bromides, PtBr2 [13455-12-4] and PtBr ... 

A chloride-bridged Zn-V-Zn trimer contains terminal triphenylphosphine ligands bound to a tetrahedral zinc, each zinc with two bridging chloride and a terminal chloride. 17... 

Zinc halide complexes with acetophenone have been structurally characterized and form monomeric or polymeric structural motifs.346 The bromide and iodide derivatives are monomeric and the chloride derivative is a coordination polymer with bridging chlorides. 

The structure of Sb2Cl102 probably has bridging chloride ions. 

The same complex could be obtained starting from CuC and subsequent substitution of both bridged chlorides by adding hydroxyl ions. Scheme 3 describes the formation and interconversion of both binuclear copper complexes. 

The simple motion of a bridging chloride from Pt(IV) to Pt(II) concomitant with motions of the exterior chloride ions effects the reversal of the oxidation states of the metal. Satisfactory though the insight implied by the above may be, it does not cover the important question of what the activation barrier to... 

Since 1972, complexes of lanthanides with cyclic sulfoxides have received considerable attention. Zinner and Vicentini (261) have reported the complexes of lanthanide perchlorates with TMSO. The L M in these complexes decreases along the lanthanide series. But in the case of complexes of lanthanide chlorides with TMSO, the L M increases from 2 1 for the lighter lanthanides to 3 1 for the heavier lanthanides (262). It has been suggested that these complexes, especially the bis-TMSO complexes, contain bridging chloride ions. Tetrakis-TMSO complexes with lanthanide isothiocyanates have also been reported (263). 

The anions in the complexes of DMSO and DMF with lanthanide chlorides are coordinated (43, 252). In DMF both these series of complexes behave as 1 1 electrolytes showing the presence of one replaceable chloride ion. This chloride is probably weakly bound compared to the other two chloride ions. These results were explained by assuming the presence of bridging chloride ions in these complexes. Results obtained for the complexes of TMSO with lanthanide chlorides have been explained in a similar fashion (262). 

AljClg, a dinuclear complex with bridging chloride ions. 

Relaxation of the electron spins of the exchange coupled trimeric copper cluster octachlorodiadeniniumtricopper(II) was observed58 by measuring the EPR spectra at X-band and 190 GHz as a function of temperature. This was an example of an extra relaxation mechanism available to a cluster compared to an isolated ion. In this complex the three Cu(II) ions are linked in a linear fashion by the bridging chloride ions. The HFEPR spectra at room temperature showed three lines with Q = 2.056, g2 = 2.141 and g3 = 2.204. By 5 K the values were g — 2.027, g2 = 2.135 and g — 2.230. The shift in the values of g, and g3 with... 

Beryllium is normally divalent in its compounds and, because of its high ionic potential, has a tendency to form covalent bonds. In free BeX2 molecules, the Be atom is promoted to a state in which the valence electrons occupy two equivalent sp hybrid orbitals and so a linear X—Be—X system is found. However, such a system is coordinatively unsaturated and there is a strong tendency for the Be to attain its maximum coordination of four. This may be done through polymerization, as in solid BeCk, via bridging chloride ligands, or by the Be acting as an acceptor for suitable donor molecules. The concept of coordinative saturation can be applied to the other M"+ cations, and attempts to achieve it have led to attempts to deliberately synthesize new compounds. 

Dinuclear carbonyl anions [M2(CO)8X3] were obtained through a two-electron transfer to protons by treatment of [M(CO)6]- with HX (X = Cl, OAc, OMe) (equation 82).526 The anion has Civ symmetry. The niobium atoms are heptacoordinated with four terminal carbonyl groups each and three bridging chlorides located at the vertices of an approximately equatorial... 

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