Spectroscopic and theoretical studies of potassium sodium l -(+)-tartrate tetrahydrate and l -tartaric acid used as precursors for in situ laser-induced deposition of the catalytically active copper microstructures

In this work we study the influence of l -(+)-КNaC 4 H 4 O 6 × 4H 2 O (KNaT) and l -H 2 C 4 H 4 O 6 (H 2 T) on the complexation processes occurring during in situ laser-induced catalytic destruction of the organic components of the aqueous solutions with formation of the unsaturated hydrocarbons. For that purpose, ATR-FTIR, Raman, IR, and NIR spectroscopy as well as quantum chemical calculations were implemented. It was observed that hydration of T 2− anion via carboxylate groups is stronger than that via hydroxyl groups. We also established the changes in the spectral characteristics of the absorption bands corresponding to vibrations of T 2− , HT − , and H 2 T, at solid state-liquid and acid-salt transitions, depending on concentration of the solution components and the [OH − ]/[H 2 T] ratio. Finally, it was shown that ethylene is a main product of the catalytic destruction of the copper tartrate complexes.