Mass¶
periodictable.mass
¶
Adds average mass for the elements:
- mass, mass_units (u)
- The molar mass averaged over natural isotope abundance.
Adds mass and abundance information for isotopes:
- mass, mass_units (u)
- The molar mass of the individual isotope.
- abundance, abundance_units (%)
- Natural abundance for the isotope.
Atomic Weights and Isotopic Composition [1].
The atomic weights are available for elements 1 through 112, 114, & 116 and isotopic compositions or abundances are given when appropriate. The atomic weights data were published by Coplen [2] in Atomic Weights of the Elements 1999, (and include changes reported from the 2001 review in Chem. Int., 23, 179 (2001)) and the isotopic compositions data were published by Rosman [3] and Taylor [4] in Isotopic Compositions of the Elements 1997. The relative atomic masses of the isotopes data were published by Audi [5] and Wapstra [6] in the 1995 Update To The Atomic Mass Evaluation.
This data has been compiled from the above sources for the user’s convenience and does not represent a critical evaluation by the NIST Physics Laboratory. http://physics.nist.gov/PhysRefData/Compositions/
Neutron mass from NIST Reference on Constants, Units, and Uncertainty http://physics.nist.gov/cuu/index.html
[1] | Coursey. J. S., Schwab. D. J., and Dragoset. R. A., NIST, Physics Laboratory, Office of Electronic Commerce in Scientific and Engineering Data. |
[2] | Coplen. T. B. : U.S. Geological Survey, Reston, Virginia, USA. |
[3] | Rosman. K. J. R. : Department of Applied Physics, Curtin University of Technology, Australia. |
[4] | Taylor. P. D. P. : Institute for Reference Materials and Measurements, European Commission, Belgium. |
[5] | Audi. G. : Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse, Orsay Campus, France. |
[6] | Wapstra. A. H. : National Institute of Nuclear Physics and High-Energy Physics, Amsterdam, The Netherlands. |
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periodictable.mass.
abundance
(isotope)¶ Natural abundance.
Parameters: isotope : Isotope Returns: abundance : float | % - Reference:
- Coursey. J. S., Schwab. D. J, and Dragoset. R. A., NIST Atomic Weights and Isotopic Composition Database.
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periodictable.mass.
init
(table, reload=False)¶ Add mass attribute to period table elements and isotopes
-
periodictable.mass.
mass
(isotope)¶ Atomic weight.
Parameters: isotope : Isotope
Returns: - mass : float | u
Atomic weight of the element.
- Reference:
- Coursey. J. S., Schwab. D. J, and Dragoset. R. A., NIST Atomic Weights and Isotopic Composition Database.