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== Characterization of CdSe ==
 
While there are many techniques to perform a quantitative analysis, here we will focus on two of the more common tools for material analysis: X-Ray Diffraction (XRD) and Ultraviolet-visible spectroscopy (UV-Vis) analyses.
 
X-Ray Diffraction Analysis-XRD is a common tool used to analyze and characterize different materials and their properties. The procedure sees a small powder or thin film sample loaded into an X-Ray diffractometer and then exposed to X-Rays. The angle at which the incident rays meet the sample and the angle at which the diffracted rays are caught by the detector are changed periodically during the test. [Image of Diffractometer should be here]. This is because different materials will have different positions where the energy diffracted toward the detector is at its highest, these will form the peaks we see on diffractograms. [Need to insert short discussion on what can be learned from diffractograms and Bragg’s Law]
 
[Image of CdSe diffractogram should be here] The above figure is a diffractogram of a sample of CdSe Quantum Dots given by an XRD test along with an overlay of the diffraction pattern of CdSe provided by the International Center for Diffraction Data. [Need to build on discussion for results i.e. the spread of peaks vs. diffraction card].
 
Ultraviolet-visible spectroscopy tests examine the absorption or reflective spectroscopy of a material over the ultraviolet-visible spectral region. The test itself bombards a sample of a material with light of varying wavelengths in a spectrophotometer, as it’s exposed to different light the spectrophotometer monitors the intensity at which the sample absorbs (or reflects) the light at these different wavelengths. And with the help of logging software it can produce spectrographs like the one below:
[Image of UV-Vis spectrograph and WL chart]
[Need discussion points for spectrograph]
== Design ==
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