Electronic properties of ThC^- and ThC

Area of Science:

• Computational chemistry
• Quantum chemistry
• Molecular physics

Background:

• Understanding the electronic structure and properties of heavy element compounds is crucial.
• Thorium carbide (ThC) and its anion (ThC⁻) are of interest due to their unique chemical bonding and potential applications.

Purpose of the Study:

• To investigate the low-lying electronic states of ThC⁻ and ThC.
• To determine spectroscopic constants, electron configurations, and energetics.
• To analyze spin-orbit coupling effects.

Main Methods:

• Multireference calculations
• Coupled-cluster approaches
• Large correlation-consistent basis sets

Main Results:

• Characterization of 9 states for ThC⁻ and 18 states for ThC.
• Identification of ground states as 2Σ+1/2(I) for ThC⁻ and 3Σ+1(I) for ThC.
• Calculated adiabatic detachment energy (ADE) of 1.591 eV and vertical detachment energy (VDE) of 1.604 eV for ThC⁻ → ThC.
• Predicted dissociation energy (D₀) of 5.099 eV for ThC.
• Estimated standard enthalpy of formation (ΔfH°(298 K)) of ThC as 822.52 ± 6 kJ mol⁻¹.

Conclusions:

• The study provides a comprehensive theoretical investigation of ThC⁻ and ThC electronic properties.
• Calculated values offer benchmarks for experimental validation and further theoretical studies.
• The findings contribute to the understanding of bonding and reactivity in heavy element compounds.