XAFS study of Cu2+ in aqueous solution of CuBr2

SYNCHROTRON TECHNOLOGY AND APPLICATIONS

XAFS study of Cu²⁺ in aqueous solution of CuBr₂

DAI Binbin，

WANG Qian，

MA Jingyuan，

LI Jiong，

ZHANG Shuo，

HUANG Yuying，

HUANG Wei，

WU Guozhong，

ZOU Yang，

JIANG Zheng，

XU Hongjie

Nuclear Science and Techniques

Vol.23, No.3

pp.129-133

Published in print 20 Jun 2012

DOI：10.13538/j.1001-8042/nst.23.129-133

35000

Copper ion is the essential microelement to many organisms. In this paper, the local structure of Cu²⁺ in CuBr₂ aqueous solutions with different concentrations are investigated by using X-ray absorption fine structure (XAFS) technique. XANES (X-ray Absorption Near Edge Structure) spectra indicate that charge transfer from Br^- to Cu²⁺ decreases with the solution concentration, which lead to a shift of the absorption edge. The shoulder appearing at the rising edge proves to be characteristic of a tetragonal distortion. The Fourier transform magnitudes of EXAFS (Extended X-ray absorption fine structure) data of Cu species suggest that more Cu-Br bonds may exist in high concentrations. A fivefold coordination configuration like a pyramid is used as the fitting parameters. From the analysis of the coordination numbers, the proportion of Cu-O and Cu-Br is 4:1 in the saturated solution. The Br atom is on the equatorial plane of the model. The fitting results agree well with the experiment data.

CuBr2Aqueous solutionXAFScoordination

References

[1]

D'Angelo P, Barone V, Chillemi G, et al. J Am Chem Soc 2002, 124: 1958-1967.

[2]

Dang LX, Schenter GK, Fulton JL. J Phys Chem B, 2003, 107: 14119-14123.

[3]

Salmon PS, Neilson GW. Journal of Physics-Condensed Matter, 1989, 1: 5291-5295.

[4]

Becaria A, Bondy SC, Campbell A. Journal of Alzheimer's Disease, 2003, 5: 31-38.

[5]

Kucharzewski M, Braziewicz J, Majewska U, et al. Biol Trace Elem Res, 2003, 93: 9-18.

[6]

Miesel R, Zuber M. Inflammation, 1993, 17: 283-294.

[7]

Kau L S, Spira-Solomon D J, Penner-Hahn J E, et al. J Am Chem Soc, 1987, 109: 6433-6442.

[8]

Chaboy J, Munoz-Paez A, Carrera F, et al. Phys Rev B, 2005, 71: 134208.

[9]

Berry A J, Hack A C, Mavrogenes J A, et al. Am Mineral, 2006, 91: 1773-1782.

[10]

Corami A, D'Acapito F, Mignardi S, et al. Materials Science and Engineering B-Advanced Functional Solid-State Materials, 2008, 149: 209-213.

[11]

Frank P, Benfatto M, Szilagyi R K, et al. Inorg Chem, 2007, 46: 7684-7684.

[12]

Korshin G V, Frenkel A I, Stern E A. Environmental Science & Technology, 1998, 32: 2699-2705.

[13]

Garcia J, Benfatto M, Natoli C R, et al. Chem Phys, 1989, 132: 295-302.

[14]

Okan S E, Salmon P S. Mol Phys, 1995, 85: 981-998.

[15]

Pasquarello A, Petri I, Salmon P S, et al. Sci, 2001, 291: 856-859.

[16]

Benfatto M, D'Angelo P, Della Longa S, et al. Phys Rev B, 2002, 65: 174205/174201-174205.

[17]

Frank P, Benfatto M, Szilagyi R K, et al. Inorg Chem, 2005, 44: 1922-1933.

[18]

Bryantsev V S, Diallo M S, van Duin A C T, et al. The Journal of Physical Chemistry A, 2008, 112: 9104-9112.

[19]

Mo L P, Ma Z C, Zhang Z H. Synth Commun, 2005, 35: 1997-2004.

[20]

King L C, Ostrum G K. The Journal of Organic Chemistry, 1964, 29: 3459-3461.

[21]

Bhatt S, Nayak S K. Synth Commun, 2007, 37: 1381-1388.

[22]

Onori G, Santucci A, Scafati A, et al. Chem Phys Lett, 1988, 149: 289-294.

[23]

Palladino L, Dellalonga S, Reale A, et al. J Chem Phys, 1993, 98: 2720-2726.

[24]

Shivaiah V, Das S K. Angew Chem Int Ed, 2006, 45: 245-248.

[25]

Meijuan Y, Wangsheng C, Xing C, et al. Journal of Physics: Conference Series, 2009, 190.

[26]

Fontaine A, Lagarde P, Raoux D, et al. Phys Rev Lett, 1978, 41: 504-507.