Spectroscopic properties and molecular structure of copper phytate complexes: IR, Raman, UV–Vis, EPR studies and DFT calculations

Abstract

The copper phytate IP6Cu, IP6Cu 2 and IP6Cu 3 complexes were synthesized changing the phytate to metal mole ratio. The obtained products have been characterized by means of chemical and spectroscopic studies. Spectroscopic ATR/IR, FT-Raman, UV–Vis, EPR and magnetic measurements were carried out. The structures of these compounds have been proposed on the basis of the group theory and geometry optimization taking into account the shape and number of the bands corresponding to the stretching and bending vibrations of the phosphate group and metal–oxygen polyhedron. The role of the inter- and intra-hydrogen bonds in stabilization of the structure has been discussed. EPR studies showed that a local rhombic symmetry of copper ions appears in the studied phytates. Dominant interactions show antiferromagnetic properties depending on the content of paramagnetic ions. Electronic supplementary material The online version of this article (10.1007/s00775-018-1622-0) contains supplementary material, which is available to authorized users.

Role of metal complexation on the solubility and enzymatic hydrolysis of phytate

“…In summary, the reactivity of phytate and the inhibitory effects of metal ions on the hydrolysis by phytase significantly affect the fate of phytate and other inositol phosphates. It should be pointed out that advanced spectroscopic techniques have shown different conformational structures of phytate complexed with different metals with particular distinction among mono-and multi-valent ions [53][54][55]. Future research on developing the relationship of conformational structure to hydrolysis and impact of released metal will help develop the mechanistic relationship and provide insights on the availability of phytate in soil and other environments.…”

Stability, spectroscopic, electrochemistry and QTAIM analysis of Cu-Znn−1On clusters for glucose sensing application: A study on theoretical and experimental insights

“…The peaks in the range of 3750–3626 cm −1 and 3840 cm −1 (weak) are attributed to O–H stretching modes in the glucose ring of the Zn 2 O 2- glucose complex, while this peak (Zn–O–H) drastically decreases to 3367 cm −1 (strong) in the Cu–ZnO 2 -glucose complex due to the hydrogen bonding with the carbonyl group (Zn–O–H⋯O=CH-) ( Figure 9 ) [ 55 , 56 ]. In the IR spectra of the complexes, the observation of non-hydrogen bonding OH stretching peaks at higher frequencies and hydrogen bonding OH stretching peaks at lower frequencies is also consistent with the literature [ 55 , 56 ]. Unlike the Zn 2 O 2 -glucose complex, the peak, which was detected at 1647 cm −1 , is attributed to the stretching vibration of the carbonyl group in the Cu–ZnO 2 -glucose complex [ 55 ].…”

On the Origins of Some Spectroscopic Properties of “Purple Iron” (the Tetraoxoferrate(VI) Ion) and Its Pourbaix Safe-Space

“…These M 3 (BO 3 ) 2 complexes bear magnetic properties with many useful applications. On another occasion, Zajac et al (2019) copper phytate complexes were studied by a combination of ATR (Attenuated Total Reflection)/Infrared, FT-Raman, UV–Vis, EPR spectroscopies, magnetic measurements and DFT calculations [ 156 ]. Studying phytic acid is important because the compound has adverse medical implications.…”