Rapid weightless determination of the atomic ratio of iron and platinum in ferrocene derivatives by x-ray fluorescence analysis

Abstract

When developing new organometallic compounds, the necessity for a rapid control of the elemental composition of the substances obtained arises at different stages of synthesis. This makes urgent the goal of speeding up the procedure of elemental analysis. The XFA method is traditionally used in the laboratory for microanalysis when determining the metal content in the substance composition according to the method of an external standard with a dilution of the substance sample with emulsion polystyrene. Precise weighing of the sample and diluent is required in the manufacture of analyzed reflector samples, since a dilution factor is needed to calculate the content of the elements. When synthetic chemists are interested in the atomic ratio of metals included in the organic matrix rather than in the exact elemental composition of the resulting compound, we propose to eliminate the lengthy weighing procedure and use measured amounts of substances in the manufacture of the analyzed samples. The developed technique is tested on a number of ferrocene derivatives containing platinum atoms, and a rapid weightless method for determining the atomic ratios of Fe and Pt in synthesis products is proposed. Analytical signals were measured on an X-ray fluorescence spectrometer SPECTROSCAN MAX-GVM (NPO Spectron LLC, St. Petersburg) at the wavelengths of FeKα and PtLα lines in the 40 kV/0.5 mA mode. The metal content in the emitter samples was determined by the calibration equations. Simplification of the spectrometry procedure and the absence of weighing significantly speeds up the procedure. The proposed method can be used as a preliminary criterion for success synthesis of the desired product before the complete elemental analysis of the latter.