Molecular modelling of Me(2+)-(8-hydroxy-quinolinate)2 complexes using ZINDO and ESSF methods

Area of Science:

• Computational Chemistry
• Coordination Chemistry

Background:

• Metal-organic complexes play vital roles in various chemical and biological systems.
• Understanding the formation and properties of these complexes is crucial for developing new materials and applications.

Purpose of the Study:

• To evaluate the suitability of semi-empirical (ZINDO) and molecular mechanics (ESFF) methods for studying bivalent metal-8-hydroxy-quinolinate systems.
• To investigate the mechanisms of complex formation and identify computational tools for designing chelating agents.

Main Methods:

• Utilized ZINDO and ESFF computational methods to model Me2+ (8-hydroxy-quinolinate)1-2 complexes.
• Studied a range of bivalent metals, including alkaline earth metals and first/second-row transition metals.
• Performed structural and spectral validation of the computational models.

Main Results:

• ESFF accurately predicted complex structures.
• ZINDO demonstrated superior capability in describing complex formation mechanisms and spectral properties.
• Established correlations between SCF energies, equilibrium constants, and computed charges with pH, supporting ZINDO for chelating agent design.

Conclusions:

• ZINDO is a valuable tool for understanding metal-8-hydroxy-quinolinate complex formation mechanisms.
• Computational methods, particularly ZINDO, can guide the rational design of novel chelating agents.
• The computational cost is feasible for comprehensive metal investigations.