Na-21 Zeeman Effect
AIM
To demonstrate the splitting of spectral lines under the influence of a magnetic field.
APPARATUS
- Electromagnet
- Electromagnet Control Unit
- Tunable DC Power Supply 6A
- Fabry-Perot Interferometer
- Mercury Lamp
- Laptop Computer
- Capstone Software
DESCRIPTION
A mercury lamp is position at the centre of an Electromagnet. A hole has been drilled through the centre of the soft iron core so that the spectrum of the mercury lamp can be observed, parallel to the magnetic field. The mercury spectrum can also be observed perpendicular to the magnetic field. When the mercury lamp is switched on. A set of concentric rings is observed on the computer screen via a video camera, which is an image of the mercury spectrum that is produced by the lens and Fabry-Perot Interferometer. The concentric rings are the 546.1 nm green spectral line in mercury is due to a transition of an electron from a 3S1(6s7s) energy level to a 3P2(6s6p) level. The (6s7s) notation means that mercury has two valence electrons; one in a 6s orbital and one in a 7s orbital. When a magnetic field is applied to the mercury spectrum. Splitting of the concentric ring will be observed. The greater the magnetic field the greater the splitting of the concentric ring. When the spectrum is observed perpendicular the magnetic field, 2 rings will be observed with original spectrum ring remaining the same position.
When the spectrum is observed parallel the magnetic field, only 3 rings will be observed, with the original ring just separated into 2 rings and spreading from the original position.
The splitting of spectral lines demonstrates the quantum angular moments states of electrons in their orbit states.