High-resolution photoelectron spectroscopy of cryogenically cooled SiC

Area of Science:

• Physical Chemistry
• Atomic and Molecular Physics
• Spectroscopy

Background:

• Silicon carbide (SiC) is a vital material in various technological applications.
• Understanding the electronic structure of SiC anions and neutral states is key to predicting its chemical behavior.

Purpose of the Study:

• To investigate the electronic structure of silicon carbide (SiC) anions.
• To determine the electron affinity (EA) of SiC and its spectroscopic constants.
• To explore the fine structure of neutral SiC states.

Main Methods:

• High-resolution photoelectron spectroscopy.
• Cryogenic ion trap technique.
• Slow-electron velocity-map imaging.

Main Results:

• Observed photodetachment transitions to the ground (X 3Π) and excited states (a 1Σ+, b 1Π) of neutral SiC.
• Resolved the fine structure of the SiC X 3Π band.
• Identified a long-lived excited state (A 3Π) of SiC- at 3380(101) cm-1.
• Determined the electron affinity of SiC: EA(SiC) = 19,327(15) cm-1 (2.396(2) eV).
• Derived spectroscopic constants for the SiC- ground state (X' 2Σ+): ωe = 1016(21) cm-1 and ωexe = 5.20(22) cm-1.

Conclusions:

• The study provides precise spectroscopic data for SiC anions and neutral states.
• The determined electron affinity and spectroscopic constants enhance the understanding of SiC's electronic properties.
• This research contributes to the fundamental knowledge of small carbon-containing molecules.