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fine structure

[fahyn] /faɪn/
noun, Physics.
a group of lines that are observed in the spectra of certain elements, as hydrogen, and that are caused by various couplings of the azimuthal quantum number and the angular momentum quantum number.
Origin of fine structure
1915-20 Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for fine structure
  • The good news is that the signal has an amazing wealth of fine structure imposed by its environment.
  • Plus, the fact that the fine structure constant is small.
  • He put some of the tissue under a microscope to look at its fine structure.
  • For example, a graph showing the range of possible fine structure constant and then the chance each interval would be represented.
British Dictionary definitions for fine structure

fine structure

the splitting of a spectral line into two or more closely spaced components as a result of interaction between the spin and orbital angular momenta of the atomic electrons Compare hyperfine structure
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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