Copper complexes EXAFS spectroscopy

Entering group effect platinum complexes substitution reactions, 494 EXAFS spectroscopy cadmium complexes, 929 copper(II) complexes, 720 zinc complexes, 929... 

Peacock, C. L., and Sherman, D. M. (2004a). Copper(II) sorption onto goethite, hematite, and lepidocrocite a surface complexation model based on ab initio molecular geome-hies and EXAFS spectroscopy. Geochim. Cosmochim. Acta 68, 2623-2637. 

EXAFS spectroscopy, as well as magnetic properties turns to be very sensitive to the fixation of two ammonia molecules (Fig. 11b, d) increased complexity of the spectrum, particularly for Peaks 2 and 3, at both Cu and Br edges, reduced intensity of the Cu—Br Peak 4. These observations can be related simply to a site distortion of the square CuO entity, leading to a copper surroundings with 4 short bonds (2 Cu—N... 

EXAFS spectroscopy may be used to determine, in ideal situations, the lenmh and number, n, of the Cu—L distances, but while the distances may be reliable to 0.01 A, the n value may only be correct to one unit on three or four ligands. A dicarbonyl copper(I) complex may be prepared by addition of the ligand L (150) to Cul in dry methanol under a CO atmosphere it crystallizes as [ Cu(CO) 2(L )](BPli4)2. EXAFS spectroscopy yielded evidence for Cu—N distances of 2.09 A for this copper(I) complex with a reasonable Cu—Cu distance of 6.0 A. In solutions of CuCN-l-NaCN the spectra are best fitted as shown in Table 14(a) the short Cu—C distances of 1.95 A indicate Cu-carbon coordination of the CN anions and the formation of tri- and tetra-cyano copper(I) species dependent upon the Cu/CN ratio. EXAFS spectroscopy may be used to show that in the solid state the Cu atom environment can change upon electrolysis (Table 14b). In the Cul-sulfonium 1 electrolyte the Cu atom environment is changed from four I" anions before electrolysis to three 1 anions after electrolysis (Table 14b). 

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