X-Ray Diffraction
PHYS 3P91
X-ray fluorescence Electron Diffraction
Professor: Dr. F. Razavi Lab Demonstrator: J. Korobanik Lab Partner: Adam Kober
Author : Jasper D’Agostino SN : 4656534
Contents
1 Introduction 1.1 X-ray fluorescence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Electron diffraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Discussion 2.1 X-ray fluorescence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Electron diffraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3 3 4 4 7
1
1.1
Introduction
X-ray fluorescence
X-ray fluorescence is a technique for investigating the elemental and chemical properties of a given physical sample. When X-rays are incident on the surface of a crystalline lattice, some of the x-rays are absorbed by atoms present in the sample. This results in a production of X-rays with a characteristic energy that depends on the atomic property of the element. An incident X-ray with energy hν0 will be absorbed by some atom and emitted with some new energy hνj , in which this new energy is directly related to the absorber atoms in the sample. A photoelectric effect occurs when an X-ray photon is incident with an atom present in the sample where photon is annihilated and the atom becomes ionized. The atom undergoes a de-exitation to its ground level energy state when the atom binds with a nearby electron. This effect can be described by an energy equation given by K − hν0 − B where K is the kinetic energy of the photoelectron, and B is its binding energy. During the de-exitation of the atom to its ground state, characteristic X-ray photons are produced directly related to the properties of the atom undergoing energy change. To obtain accurate spectroscopic data for unkown samples, known samples must be used as a cailbration guide. Using the Molybdenum source X-ray emitter, detector, and programmable MCA (Multi Channel Analyzer), we were able to smash known
X-ray fluorescence Electron Diffraction
Professor: Dr. F. Razavi Lab Demonstrator: J. Korobanik Lab Partner: Adam Kober
Author : Jasper D’Agostino SN : 4656534
Contents
1 Introduction 1.1 X-ray fluorescence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.2 Electron diffraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Discussion 2.1 X-ray fluorescence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.2 Electron diffraction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3 3 4 4 7
1
1.1
Introduction
X-ray fluorescence
X-ray fluorescence is a technique for investigating the elemental and chemical properties of a given physical sample. When X-rays are incident on the surface of a crystalline lattice, some of the x-rays are absorbed by atoms present in the sample. This results in a production of X-rays with a characteristic energy that depends on the atomic property of the element. An incident X-ray with energy hν0 will be absorbed by some atom and emitted with some new energy hνj , in which this new energy is directly related to the absorber atoms in the sample. A photoelectric effect occurs when an X-ray photon is incident with an atom present in the sample where photon is annihilated and the atom becomes ionized. The atom undergoes a de-exitation to its ground level energy state when the atom binds with a nearby electron. This effect can be described by an energy equation given by K − hν0 − B where K is the kinetic energy of the photoelectron, and B is its binding energy. During the de-exitation of the atom to its ground state, characteristic X-ray photons are produced directly related to the properties of the atom undergoing energy change. To obtain accurate spectroscopic data for unkown samples, known samples must be used as a cailbration guide. Using the Molybdenum source X-ray emitter, detector, and programmable MCA (Multi Channel Analyzer), we were able to smash known
References: [1] Brock Physics. PHYS 3P91 Laboratory Manual, pg 5–13, 2008. P = 2π ν c 2 hν hν kT exp −1