AtomicWeights

 Author: Kurt Pagani
 Date Created: Fri Jun 01 01:30:45 CEST 2018
 License: BSD
 References:
   https://www.nist.gov/pml/
     atomic-weights-and-isotopic-compositions-relative-atomic-masses
   https://physics.nist.gov/cgi-bin/Compositions/
     stand_alone.pl?ele=&all=all&ascii=ascii2&isotype=all
   https://www.nist.gov/pml/
     atomic-weights-and-isotopic-compositions-version-history
   Cite as:
   Coursey, J.S., Schwab, D.J., Tsai, J.J., and Dragoset, R.A. (2015),
   Atomic Weights and Isotopic Compositions (version 4.1). [Online]
   Available: http://physics.nist.gov/Comp [year, month, day].
   National Institute of Standards and Technology, Gaithersburg, MD.
 Description:

   Raw data (@end)
   Sample:
      Atomic Number = 1
      Atomic Symbol = H
      Mass Number = 1
      Relative Atomic Mass = 1.00782503223(9)
      Isotopic Composition = 0.999885(70)
      Standard Atomic Weight = [1.00784,1.00811]
      Notes = m

   ==> ["H1",["1","H","1","1.00782503223(9)","0.999885(70)",
                             "[1.00784,1.00811]","m"]]$RKE,_