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Structural and conductivity studies of Ge-S-AgI glasses B. Monchev1, T. Petkova1, P. Petkov2 and I. Kanazirski3 1 Institute of Electrochemistry and Energy Systems, Bulgarian Academy of Sciences, Sofia, Bulgaria Corresponding author: [email protected] 2 Laboratory of Thin Film Technology, University of Chemical Technology and Metallurgy-Sofia, Bulgaria 3 Department of Physic-chemistry, University of Chemical Technology and Metallurgy-Sofia, Bulgaria The structure of the amorphous materials with compositions (GeSx)100-yAgIy with x= 1,2 ; 1,5 and y = 5, 10, 15, 20 mol.% has been studied by IR spectroscopy with respect to their application. Interesting conductivity results in Ge-S-AgI non-crystalline materials has been detected. FTIR analysis XRD Conductivity Observed IR Bands Literature IR Bands Region 100-200 109 – 110 Molar Volume Number density Ea Composition cm-1 148-151 cm-1 105-110 cm-1 = Ag+ ions [2,4] 110 cm-1 = υ2(E)GeS4/2 [2] 100-110 cm-1 = AgI [9] [ m3/mol] x1028 [atoms/m3] [eV] 185 – 188 cm-1 147-153 cm-1 = υ4(F2)GeS4/2 [2,5,7] 180-190 cm-1 = Ag2S [7,9] (GeS1,2)90(AgI)10 1,78 3,38 0,31 Region 200-300 232 – 240 cm-1 230-240 cm-1 = Ag2S [9] 251 cm-1 = Ge-S-I linkages [1] 259 cm-1 (GeS1,2)80(AgI)20 1,97 3,06 255-260 cm-1 = S3Ge-GeS3 [3,4] 0,27 275 – 279 cm-1 270 cm-1 = meta(Ge-S-Ge) [2] Region 300-400 (GeS1,5)90(AgI)10 1,80 3,35 0,29 306 – 313 cm-1 336 – 339 cm-1 378 – 379 cm-1 (GeS1,5)80(AgI)20 2,19 2,75 0,43 328-327 cm-1 = υ1(A1)GeS4/2 [2,3,5] 377-380 cm-1 = υ3(F2)GeS4/2 [2,3] 360-380 cm -1 = GeS1/2S33- [4] Region 400-500 412 – 417 cm-1 405 cm-1 = Ge-S-I linkages [1] Conclusions References [1] J. Heo, J. Mackenzie, J. Non-Cryst. Sol. 113 (1989) 246. [2] E. Kamitsos, J. Kapoustis, G. Chryssikos, A. Pradel, M. Ribes, J. Sol. State Chem. 112 (2) (1994) 255. [3] C. Julien, S. Barnier, M. Massot, N. Chbani, X. Cai, A.M. Loireau-Lozac’h, M. Guittard, Materials Science and Eingineering B 22 (1994) 191. [4] Q. Mei, J. Saienga, J. Schrooten, B. Meyer, S. Martin, J. Non-Cryst. Sol. 324 (2003) 264. [5] G. Lukovsky, F.Galeener, R. Keezer, R. Geils, H. Six, Phys. Rev. B 9 (1974) 1591. [6] A. Ibanez, E. Philippot, S. Benazeth, H. Dexpert, J. Non-Cryst. Sol. 127 (1991) 25. [7] A. Stetsun, I. Indutnyi, V. Kravets, J. Non-Cryst. Sol. 202 (1996), 113. [8] I. Kotsalas, C. Raptis, J. Optelect. Adv. Mater. 3 (3) (2001) 675. [9] Gmelin L. (1974–1979) In: Gmelin handbook of inorganic chemistry. Springer-Verlag. [10] R. Holomb, P. Johansson, V. Mitsa, I. Rosola, Philosophical Magazine 85 (25) (2005) 2947. The basic structural units detected are GeS4/2 tetrahedra, S3-Ge-Ge-S3 formations and Ge-S-I linkages ! Some vibrations on the spectra have been attributed to silver-iodine and silver-sulfur interactions in complex silver-chalcogenide fragments ! Silver-based formations are most probable reason for the registered broad bands as revealed peaks fitting ! Conductivity depends on the temperature and composition of the studied Ge-S-AgI materials ! Acknowledgment: The research leading to these results has received funding from the European Community’s Seventh Framework Programme (FP7/2007-2013) under grant agreement № 213389.