The electronic structure of Ti2 and Ti2(+)

Area of Science:

• Computational Chemistry
• Molecular Physics
• Quantum Chemistry

Background:

• Understanding the electronic structure and bonding of diatomic metal molecules is crucial in various chemical and physical applications.
• Titanium dimer (Ti2) and its cation (Ti2+) are of interest due to their potential catalytic and material properties.

Purpose of the Study:

• To perform a comprehensive theoretical investigation of the electronic states and potential energy curves for Ti2 and Ti2+.
• To determine spectroscopic parameters and elucidate the nature of bonding and electronic interactions within these systems.

Main Methods:

• Utilizing multireference variational and single-reference coupled-cluster methods.
• Employing large atomic basis sets for high-accuracy electronic structure calculations.
• Constructing potential energy curves for numerous electronic states of Ti2 and Ti2+.

Main Results:

• Identified van der Waals minima in Ti2 potential energy curves around 7 bohr, independent of molecular symmetry.
• Observed significant 4s electron interactions (4s(2)-4s(1)) in Ti2+ around 6 bohr, leading to stronger covalent bonds.
• Characterized the ground state of neutral Ti2 as a (3)Δ(g) state, with the first excited state closelying in energy (within 1 kcal/mol).
• Determined the ground state of Ti2+ to be an X(2)Σ(g)(+) state.

Conclusions:

• The electronic structure of Ti2 and Ti2+ is characterized by distinct van der Waals and covalent interactions.
• Computational methods provide valuable insights into the spectroscopic properties and bonding of these diatomic titanium species.
• The findings contribute to a deeper understanding of the fundamental electronic behavior of transition metal dimers.