Nanocomposites and nanomaterials 

XRD and Raman studies of structural peculiarities of chalcogenide glasses 

Revutska L.O.1, Shportko K.V2, Stronski A.V.2, Paiuk O.P. 2, Gudymenko O.Y.2, Baran J. 3, Trzebiatowska M. 3, Gubanova A.O.4

1National Technical University of Ukraine “Igor Sikorsky Kyiv Polytechnic Institute”. Prospect Peremohy 37, Kyiv-03056, Ukraine.
E-mail: liubov.revutska@gmail.com.

2V. Lashkaryov Institute of Semiconductor Physics of the NAS of Ukraine. 
Prospect Nauky 41, Kyiv-03680, Ukraine.

3W. Trzebiatowski Institute of Low Temperatures and Structure Research, Polish Academy of Sciences, Okolna Str. 2, 50-422 Wroclaw, Poland

4Kamianets-Podilsky National University, Ogienko Str. 61, Kamianets-Podilsky-32300, Ukraine. 

Chalcogenides are attractive materials for new generation optoelectronics and for information storage media due to their remarkable properties. Information about the short-range order structure of chalcogenide glasses (CG) is particularly valuable for establishing useful correlations between their structural and macroscopic properties. It can help in the optimization of the sensitivity and relief formation processes of composite nanomultilayer structures based on As-S and As-Se alloys, which are perspective for the direct recording of optical elements [1]. The aim of this study is to perform analysis of the compositional evolution of Raman spectra and parameters of short-range order of the amorphous As-Se: Mn, Ge or S and As-S: Ag, Sb or Ge glasses. 
The X-ray diffraction profiles confirmed amorphous nature of studied CG and pair distribution function were calculated. The addition of Mn, Ge or S to As-Se glasses and addition of Ag, Sb or Ge to As-S glasses affects the position of first and second coordination spheres and it can be related with formation of new bonds in CG. 
The Raman spectra of pure and doped samples of As-S exhibit main band around at 340 cm-1 and pure and doped samples of As-Se have main band around at 230 cm-1. The studied CG contains different nanophases (structural units) and after introduction of elements to As-S and As-Se glasses, we can observe creation and evolution changes of relative concentrations of nanophases.
Thus, calculated pair distribution functions show the changing of elements concentration affects the positions of first and second coordination spheres and Raman data show that CG glasses contain different nanophases whose concentration is changing along chosen compositional cross-section. 
1.	Stronski A.V., Vlcek M., Stetsun A.I. Raman spectra of Ag- and Cu-photo-doped As40S60-xSex films // J. Non-Cryst. Solids.- 2000. -270. P. 129–136.