The key difference between Zeeman effect and Paschen Back effect is that Zeeman effect involves a small splitting compared to the energy difference between the unperturbed levels, whereas Paschen-Back effect involves the presence of an external magnetic field in which the energy levels of the atoms are split.
Zeeman effect and Paschen-Back effect are important chemical concepts in chemistry and describe the splitting patterns of spectral lines.
CONTENTS
1. Overview and Key Difference
2. What is Zeeman Effect
3. What is Paschen Back Effect
4. Zeeman Effect vs Paschen Back Effect in Tabular Form
5. Summary – Zeeman Effect vs Paschen Back Effect
What is Zeeman Effect?
Zeeman effect can be described as the effect of splitting a spectral line into several components in the presence of a static magnetic field. This phenomenon was named after the Dutch physicist Pieter Zeeman in 1896. He also received a Noble Prize for this discovery. The Zeeman effect is analogous to the Stark effect in the splitting of a spectral line into several components when there is an electric field, whereas it is similar to the Stark effect in the transition between different components.
Figure 01: Zeeman Effect of Mercury Vapor Lamp
The distance between Zeeman sub-levels is a function of magnetic field strength. Therefore, we can use the Zeeman effect to measure magnetic field strength. For example, measuring the magnetic field strength of the Sun and other stars.
There are many important applications of the Zeeman effect, such as nuclear magnetic resonance spectroscopy, electron spin resonance spectroscopy, magnetic resonance imaging, etc. Moreover, we can use it to improve the accuracy of atomic absorption spectroscopy. Furthermore, if the spectral lines are absorption lines, then we can call it as inverse Zeeman effect.
What is Paschen Back Effect?
Paschen Back effect can be described as the pattern created by a large magnetic field that can disrupt the coupling between the orbital and spin singular momenta, resulting in a different pattern of splitting. This effect was introduced by the two German Physicists, Paschen and Ernst Back in 1921.
This effect can generalize the magnetic fields of arbitrary strengths of the better known Zeeman effect. Moreover, this effect has been successfully interpreted within the framework of quantum mechanics. Nowadays, this interpretation appears in classical textbooks of atomic or molecular spectroscopy.
What is the Difference Between Zeeman Effect and Paschen Back Effect?
Zeeman effect and Paschen-Back effect are important chemical concepts in chemistry that describe the splitting patterns of spectral lines. The key difference between Zeeman effect and Paschen Back effect is that Zeeman effect involves a small splitting compared to the energy difference between the unperturbed levels, whereas Paschen-Back effect involves the presence of an external magnetic field in which the energy levels of the atoms are split.
The below infographic presents the differences between Zeeman effect and Paschen Back effect in tabular form for side by side comparison.
Summary – Zeeman Effect vs Paschen Back Effect
Zeeman effect can be described as the effect of splitting a spectral line into several components in the presence of a static magnetic field. Paschen Back effect can be described as the pattern created by a large magnetic field that can disrupt the coupling between the orbital and spin singular momenta, which can result in a different pattern of splitting. Therefore, the key difference between Zeeman effect and Paschen Back effect is that Zeeman effect involves a small splitting compared to the energy difference between the unperturbed levels, whereas Paschen Back effect involves the presence of an external magnetic field in which the energy levels of the atoms are split.
Reference:
1. “Paschen-Back Effect“. Hyperphysics.Phy-Astr.Gsu.Edu.
Image Courtesy:
1. “Zeeman Effect Illus” By Warren Leywon – Own work (CC BY-SA 4.0) via Commons Wikimedia