PPT UNIT 2 spectroscopy applied physics.pptx

Spectroscopy

1. Title: Spectroscopy Contents Introduction to Spectroscopy and types of spectra Magnetic Dipole Moments Electron spin and vector Atom model Stern-Gerlach Experiment Zeeman Effect Paschen-Back Effect Stark Effect LS and JJ Coupling

2. Introduction to the Magnetic dipole moment

3. Magnetic Dipole moment

4. Atomic Magnetic Moment

5. Orbital Magnetic moment

6. Spin Magnetic moment

7. Electron spin refers to a quantum property of electrons and it also is a form of angular momentum. Furthermore, the magnitude of this angular momentum happens to be permanent. Also, the electron spin is a fundamental property just like charge and rest mass. Theory of Electron Spin The electron spin theory describes the electron as a quantum particle rather than a simple sphere as in the classical theory. Furthermore, the theory tells us about the direction of the electron spin. Moreover, it also discusses its influence on certain properties like the atom’s magnetic properties. Electron Spin Directions There are two main electron spin directions: spin up and spin down. Furthermore, the spin up and spin down direction correspond to the spinning in the +z or –z direction. Moreover, these spins (spin up and spin down) refer to the particles whose spin is equal to 1/2, i.e. for electrons. In quantum theory, an electron can be considered like a minute magnetic bar. Furthermore, one can consider spin points of an electron like the north pole of the minute bar. If two proximate electrons are characterized by similar spin direction, the formation of the magnetic field by them strengthens each other. Consequently, the gaining of a strong magnetic field takes place. If the proximate electrons have an opposite spin direction, the magnetic field that results from them would cancel each other. As such, no magnetic field would be existent. Electron Spin

8. The electron spin happens to be one of the three inherent properties of the electrons. Furthermore, the other properties are an electron’s mass and charge. Moreover, the electron spin can be simply referred to as an electron’s spinning around its axis. Where, s is equivalent to a spin vector that is quantized The spin vector is articulated as ||s|| The association of the spin quantum number (s) is with the spin angular momentum and h represents the Planck’s constant. One can articulate the spin quantum number as: S = n/2 Any non-negative integer can be n. As far as the electron spin value is concerned, the permitted values are 0, 1/2, 1, 3/2, 2, etc. The intrinsic angular momentum of Electron can be represented by quantum number 1/2 The total angular momentum s is articulated by:   Its representation can take place as: ∥S∥=   s =  n ( n +1) h −−−−−−−−− √ Formula of Electron spin

9. Vector atom model Concept of spatial quantization Spinning of electron Concept of spatial quantization

10. Stern-Gerlach Experiment

11. Zeeman Effect

12. Stark effect