Abstract: The B-spline expansion technique and the method of model potential of atom have been applied to study the properties of Stark states of lithium. Our results for Stark maps, oscillator strength distributions, avoided crossing positions and widths for Li are in good agreement with other reported theoretical calculations and experimental measurement. It shows that the method we used can be applied to investigate the properties of alkali-metal atoms in external static electric field. Finally, for the first time, we obtained the evolution of the oscillator strength spectrum of Li with varying static electric field.

Keywords: 
• B-spline /
• oscillator strength /
• avoided crossing position /
• avoided crossing width