Twelve-Nitrogen-Atom Cyclic Structure Stabilized by 3d-Element Atoms: Quantum Chemical Modeling

Area of Science:

• Computational chemistry
• Materials science
• Inorganic chemistry

Background:

• The synthesis of novel compounds with unusual stoichiometries is a key goal in materials science.
• Exploring transition metal-nitrogen compounds can lead to materials with unique electronic and structural properties.

Purpose of the Study:

• To investigate the theoretical possibility of 3d-transition metal compounds with a 1:12 metal-to-nitrogen ratio.
• To characterize the structural, electronic, and thermodynamic properties of these novel compounds.

Main Methods:

• Density Functional Theory (DFT) calculations using M06/TZVP, B3PW91/TZVP, and OPBE/TZVP functionals.
• Second-order Møller–Plesset perturbation theory (MP2) for partial calculations.
• Natural Bond Orbital (NBO) analysis and visualization of Highest Occupied Molecular Orbital (HOMO)/Lowest Unoccupied Molecular Orbital (LUMO) distributions.

Main Results:

• The study confirmed the potential existence of 3d-transition metal compounds with a 1:12 metal-to-nitrogen ratio.
• All investigated MN4 groupings exhibited a tetragonal-pyramidal structure.
• Calculated bond lengths and angles were analyzed, showing near-equality for specific elements (Ti, V, Cr, Co).
• Thermodynamic parameters and electronic properties (NBO, HOMO/LUMO) were presented.

Conclusions:

• Computational evidence supports the existence of unprecedented 1:12 metal-nitrogen compounds.
• The tetragonal-pyramidal MN4 motif is a stable structural feature.
• The employed quantum chemical methods showed good agreement, validating the findings.