Luminescence as “forbidden” electronic transitions in diamond

  • G. N. Ramachandran
  • V. Chandrasekharan


Arguments are adduced to show that the doublet centred at 4152 Å occurring in the spectrum of all fluorescing diamonds arises from ‘forbidden’ transitions analogous to the forbidden3P-1S transitions in the spectrum of C I. On the basis of this analogy, fluorescence lines are also expected to occur at about 8816 Å and 7849 Å, analogous to the3P-1D and1D-1S transitions in C I. Of these, the former should also occur in absorption, while the latter should not occur in absorption and should be emitted only if the exciting radiation has a wavelength shorter than 4152 Å. A line has actually been found at 7930 Å, satisfying the latter conditions. The former line could not be recorded being outside the limit of sensitivity of the photographic plate.


Exciting Radiation Copper Sulphate Photographic Plate Normal Configuration Fluorescence Line 
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Copyright information

© Indian Academy of Sciences 1946

Authors and Affiliations

  • G. N. Ramachandran
    • 1
  • V. Chandrasekharan
    • 1
  1. 1.Department of PhysicsIndian Institute of ScienceBangalore

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