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This paper presents the results of study of titanium-magnesium catalysts often used in polymerization processes, by photoluminescence spectroscopy (PL) in combination with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The interaction of dibutyl phthalate (DBP) with MgCl 2 was studied at DBP added /Mg = 0-1 (mol/mol). The luminescence spectra with excitation at 278 nm and the excitation spectra for main emission bands were recorded. It was shown that DBP adsorbed on magnesium chloride, both in the form of donor-acceptor complexes (D + A - ) and in the form of molecular complexes. At DBP added /Mg <0.15, the formation of D + A - complexes occur predominantly; with an increase in DBP added /Mg, the fraction of molecular complexes increases. Molecular complexes are destroyed during the treatment of the support by TiCl 4 . In this case, the structure of magnesium chloride is disordered and new coordination-unsaturated sites are formed. This work is a first attempt to apply PL spectroscopy in combination with DRIFTS spectroscopy to study titanium-magnesium Ziegler-Natta catalysts. The application of PL spectroscopy to such systems made it possible to detect interactions within and between donor molecules, which would be particularly challenging to achieve using other spectroscopic methods. Both spectroscopic methods provided crucial information about the existence of two types of complexes on the sample surface which is important for tuning the synthesis procedure of the titanium-magnesium catalysts for olefin polymerization.

Luminescent spectroscopy combined with the technique of luminescent probing with rare earth ions (europium, gadolinium, terbium) and an actinide ion (uranyl) was used to differentiate enantiopure and racemic alanine, the simplest chiral proteinogenic amino acid. Using the achiral luminescent probes, small differences between pure L and DL alanine in the solid state were strongly amplified. Based on the observed electronic transitions of the probes, the position of the triplet level of the coordinated alanine was estimated. Formation of homo- and heterochiral complexes between enantiomers of alanine and the metal ions is discussed as a possible mechanism of chiral self-discrimination., (© 2017 Wiley Periodicals, Inc.)