①

Natural width: The natural width of atomic absorption line is related to the average lifetime of excited states. The longer the lifetime of the excited atom, the narrower the natural width of the absorption line, with an average lifetime of about 10-8s. Generally speaking, its natural width is about 10-5nm.

②

Doppler broadening: It is caused by the irregular thermal motion of atoms, so it is also called thermal broadening. Doppler broadening varies with the direction of relative motion between atoms and light sources. When atoms in the ground state move towards the light source, they will absorb light with longer wavelength; On the contrary, when atoms are far away from the light source, they will absorb light with shorter wavelength. Due to the irregular thermal motion of atoms, the absorption band will be broadened, and the Doppler broadening degree is about 10-4 ~ 10-3 nm. The higher the atomization temperature, the wider the Doppler.

③

Lorentz broadening: the measured atom collides with other atoms or molecules, which makes its ground state energy level change slightly, leading to the broadening of absorption line;

④

Holtz label broadening: broadening caused by excited atomic collision of the measured elements;

⑤

Field broadening

⑥

Self-absorption broadening: broadening the spectral line will reduce the absorbance and make the determination result smaller.