X-RAY DIFFRACTION STUDY OF SOME LIQUID BINARY SOLUTIONS

P 54 ISSRNS 2012: Abstracts / Synchrotron Radiation in Natural Science Vol. 11, No 1 – 2 (2012)

X-RAY DIFFRACTION STUDY OF SOME LIQUID BINARY SOLUTIONS

A. Romaniuk^∗, H. Drozdowski, and Z. B laszczak Department of Optics, Faculty of Physics A. Mickiewicz University,

ul. Umultowska 85, 61–614 Pozna´n, Poland

Keywords: binary solution, X-ray diffraction patterns, angular intensity distributions

∗e-mail : aniam@amu.edu.pl

This paper should be treated as an introduction in the attempts to apply radial distribution func- tions in the analysis of structure of a noncrystalline system which, for example, is selected binary so- lutions: ortho-nitrotoluene, ortho-chloroanisole, or- tho-nitroanisole. Radial distribution function meth- ods are applied [1]. The radial distributions are obtained by numerical analysis, applying computer methods to experimental angular functions of inten- sity distribution I(S) (with all corrections included, and after normalization of the curves) with the help of the Fourier transform of the function I(S) [2].

Measurements were performed by the Bragg- Brentano method [3] with an automatic goniometer

Figure 1 : Models of the most highly probable mutual disposition of molecules in 10% solution of textitortho- nitrotoluene, ortho-chloroanisole, ortho-nitroanisole in 1,4-dimethylbenzene.

working in cooperation with an X-ray generator characterized with high stability of supply current and high voltage.

The angular intensity distributions of X-ray ra- diation were normalized by bringing to electron units by the computer method applying a special programme. Each function I(S) was normalized by the “oscillation method” or by the “area method,”

i.e. the oscillation of the experimental function was compared with that of the theoretical function or the areas under the experimental function were compared to those under the theoretical one. In both cases the normalization was performed for high Bragg angles of scattering.

A simple model of short-range arrangement of the molecules in liquid binary solutions studied was proposed, Fig. 1. Local, most probable manners of packing and mutual orientations of molecules within the space of the first coordination sphere are dis- cussed [4].

Because of the supposed role the ring in mu- tual configurations of molecules in liquid binary so- lutions, it seems very probable that the proposed models of local arrangement (Fig. 1) can also hold for other weakly polar derivatives of binary solutions in the liquid phase.

The approach proposed in this paper gives a good description of intermolecular interactions in liquid binary solutions and is a useful X-ray method for their analysis.

References

[1] H. Drozdowski, “Local structure and molecular cor- relations in liquid 1-methylnaphthalene at 293 K,”

Chem. Phys. Lett. 351 (2002) 53 – 60.

[2] H. Drozdowski, A. Mansfeld, “X-ray analysis of intermolecular interactions in solution of ortho- nitroanisole C7H7NO3 in 1,4-dimethylbenzene,”

Phys. Chem. Liq. 46 (2008) 255 – 262.

[3] A. Guinier, Theorie et Technique de la Radiocristal- lographie (Dunod, Paris 1986).

[4] H. Drozdowski, A. Romaniuk, “X-Ray diffraction investigation of the crystalline and liquid para- chloroanisole,” Polish Crystallogr. Meeting Wroc law 51 (2009) 272 – 27.

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