- Kirchhoff & Bunsen, 1860 with burner discovered cesium, etc.
- Balmer, 1885, formula for hydrogen spectrum
- Rydberg, independently, 1888, reciprocal relation
- 1/wavelength=RH(1/22-1/n2)
- RH=10 967 757.6/m
- now Rœ=10 973 731.568 525(73) m-1 (7ppt)
- Einstein, 1909,
, e2/c both action, ratio of 140 significant.
- Bohr, 1913, simple atomic model
- Circular (de Broglie) orbits, n=1,2,3,...
- Somewhat explained atomic spectra, like Na D line.
- Balmer/Lyman/etc series Rydberg constant
- Rœ
(1/4
0)2
me4/(43c)
- Sommerfeld, 1916, complex atomic model
- Elliptical orbits, l < n
- relativistic correction (small v/c=1/137)
- Introduced orbital angular momentum (-l
ml l)
- Introduced alpha, fine structure constant
1/137
e2/(4
0c)
- Goudsmit & Uhlenbeck, 1925, intrinsic electron spin
- needed to explain alkali fine structure
- gs = 2 arbitrary
- Dirac, 1928, Relativistic Quantum Mechanics
- gs = 2 theoretical basis (Thomas precession)
- Feynman, et al, 1947, QED
- Lamb shift, virtual particles
-
gs = 2(1+ ½/ -
0.328...(/)2 +
1.181...(/)3 -
1.510...(/)4 +...
4.39x10-12)
- Calculations require 7+72+871 diagrams---vast computer time.
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