Neutral, Anionic, and Cationic Manganese Dimers through Density Functional Theory.

Area of Science:

• Quantum chemistry
• Computational materials science
• Spectroscopy

Background:

• Manganese dimer exhibits a unique antiferromagnetic ground state among first-row transition metals.
• Previous density functional theory (DFT) studies using generalized gradient approximation contradict experimental findings for manganese dimer states.

Purpose of the Study:

• To investigate the spectroscopic properties of neutral, cationic, and anionic manganese dimers using DFT.
• To evaluate the impact of Hartree-Fock exchange percentage and exchange-correlation functionals on potential energy curves.
• To identify an accurate DFT approach for studying manganese clusters.

Main Methods:

• Density Functional Theory (DFT) calculations.
• Systematic variation of Hartree-Fock exchange percentage.
• Evaluation of different exchange-correlation functionals.
• Analysis of vertical detachment energies, ionization energies, and electron affinities.

Main Results:

• A specific hybrid exchange-correlation functional was identified.
• This functional yields results comparable to experimental measurements and high-level ab initio calculations.
• Accurate prediction of ferromagnetic and antiferromagnetic states for all three manganese dimer species.

Conclusions:

• A refined DFT methodology is established for manganese dimers.
• This approach enhances the accuracy for studying larger neutral and charged manganese clusters.
• The study provides a more reliable computational tool for manganese cluster research.