Interaction between transition metals and phenylalanine: a combined experimental and computational study.

Area of Science:

• Inorganic Chemistry
• Computational Chemistry
• Materials Science

Background:

• Transition metal complexes are crucial in catalysis and medicine.
• Phenylalanine, an amino acid, can act as a ligand in coordination chemistry.
• Understanding metal-ligand interactions is key to designing new functional materials.

Purpose of the Study:

• To synthesize and characterize transition metal complexes of phenylalanine.
• To elucidate the structural, electronic, and thermodynamic properties of these complexes.
• To investigate their magnetic and spectroscopic behavior.

Main Methods:

• Synthesis of metal-phenylalanine complexes in an aqueous medium.
• Characterization using spectroscopic (IR, UV-Vis) and thermo-gravimetric analysis.
• Computational analysis using Density Functional Theory (DFT) including geometry optimization, vibrational frequency calculations, and TD-DFT.

Main Results:

• Complexes of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) with phenylalanine were successfully synthesized and characterized.
• DFT calculations predicted square planar geometries for Mn, Co, Ni, and Cu complexes, and a distorted tetrahedral geometry for the Zn complex.
• Spectroscopic and thermal analyses confirmed the composition and absence of water, while magnetic susceptibility indicated high spin paramagnetic behavior for most complexes.

Conclusions:

• The synthesized transition metal-phenylalanine complexes are thermodynamically stable with distinct structural and electronic properties.
• DFT calculations provide accurate predictions of geometry, bonding, and electronic transitions (MLCT and d-d bands).
• The study provides a comprehensive understanding of these complexes, relevant for potential applications in coordination chemistry and materials science.