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Optical Properties of Materials

  1. Sep 22, 2009 #1
    1. The problem statement, all variables and given/known data
    Which of the following oxide materials when added to fused
    sillica (SiO2) will increase its index of refraction:
    K2O, Na2O, CaO, BaO? Why?

    Ionic radii of the ions:
    K+: 0.138 nm
    Na+: 0.102 nm
    Ca2+: 0.100 nm
    Ba2+: 0.136 nm
    Si4+: 0.040 nm
    O2-: 0.196 nm

    2. Relevant equations

    3. The attempt at a solution
    In order for the index of refraction to increase,
    the added oxide particles must be larger than those of sillica.
    I see that all of the cations radii
    are larger than the Si cation radius.
    Is that mean that all of the oxides will increase the index,
    or there is another way to decide?
    1. The problem statement, all variables and given/known data
  2. jcsd
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