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Exercise 2-6: Describe a circumstance under which an atom releases x-rays. Exercise 2-7: List the kinds of information that can be obtained by using a transmission electron microscope to analyze a sample. Exercise 2-8: Discuss the limitations of microscopy methods. Exercise 2-9: Although named a scanning tunneling “microscope”, the instrument is not really a microscope. Explain why it is not a microscope and how the STM image is actually obtained. Exercise 2-10: Describe the tunnel effect. Exercise 2-11: List and describe three ways the energy absorbed by matter may be released.

In fact, the energy is sufficient to remove electrons from inner shells of atoms. When samples are scanned with x-rays of continuously varying wavelength, the spectra are monitored for discontinuities. These discontinuities occur when the x-rays have sufficient energy to eject an inner electron. The spectra are simple because there are only a few electrons in the inner levels, giving rise to very few permitted transitions. 42 Luanne Tilstra, S. Allen Broughton, Robin S. Tanke et al. 3. Raman Spectroscopy When monochromatic radiation is scattered by molecules, a small fraction of the scattered radiation is observed to have a different frequency from that of the incident radiation; this inelastic scattering is known as the Raman effect.

8) where h is Planck’s constant, a is the size of the one-dimensional box, and m is the particle mass. The quantum number, n, is a positive integer for the state with energy En. If n = 0, then there is no particle in the box. Any real particle will have n = 1, 2, 3… Thus the energy levels increase stepwise, though the steps are not equally sized. 2. Tunneling According to classical mechanics, the location of a particle can be defined. According to quantum mechanics, there exists a function that describes the probability of the particle being in a particular region of space.