Static multipole polarisabilities and second-order Stark shift in francium

Area of Science:

• Atomic physics
• Quantum mechanics
• Theoretical chemistry

Background:

• Francium (Fr) is a highly radioactive alkali metal with limited experimental data.
• Accurate theoretical calculations are crucial for understanding its atomic properties.
• Alkali atoms share similar electronic structures, allowing for comparative studies.

Purpose of the Study:

• To calculate the multipole polarisability of the ground state of francium.
• To investigate the applicability of theoretical methods to francium and other alkali atoms.
• To determine the second-order Stark shift for francium as a function of electric field strength.

Main Methods:

• Utilizing the variational technique developed by Davison.
• Applying quantum defect theory, specifically the Bates-Damgaard method.
• Performing theoretical calculations for ground-state properties.

Main Results:

• The multipole polarisability of francium was calculated.
• The employed methods yielded reasonable results for other alkali atoms, validating the approach.
• Second-order Stark shift data for francium was generated.

Conclusions:

• The theoretical framework is robust for calculating francium's atomic properties.
• The results provide a basis for future experimental verification of francium's Stark shift.
• This study contributes to the understanding of heavy alkali metal behavior.