PtF6(2-) dianion and its detachment spectrum: a fully relativistic study

Area of Science:

• Theoretical Chemistry
• Quantum Chemistry
• Spectroscopy

Background:

• Dianions present unique electronic structures and spectral properties.
• Heavy elements necessitate relativistic treatments for accurate electronic structure calculations.
• Understanding photoelectron spectra provides insights into molecular electronic configurations.

Purpose of the Study:

• To computationally predict the gas-phase photoelectron spectrum of the PtF6(2-) dianion.
• To investigate the influence of relativistic effects and electron correlation on the spectral properties.
• To explore the role of spin-orbit coupling in the electronic structure of PtF6(2-).

Main Methods:

• Application of the third-order Dirac-Hartree-Fock one-particle propagator technique.
• Consistent theoretical treatment of relativistic effects and electron correlation.
• Basis set size and molecular geometry dependence analysis.

Main Results:

• Calculated photoelectron spectrum for PtF6(2-) with predictive character.
• Observed strong dependence on basis set size and molecular geometry, typical for dianions.
• No valence orbital inversion found, unlike in PtCl6(2-).
• Unusual strong spin-orbit splitting in the 1t1u molecular spinor noted.
• Relativistic effects lowered double ionization threshold, enabling interatomic Coulombic decay.

Conclusions:

• Spin-orbit coupling is crucial for accurately reproducing the spectral structure of PtF6(2-).
• Scalar-relativistic treatments are insufficient for understanding this system.
• Relativistic effects significantly impact electronic structure and ionization processes in PtF6(2-).