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Periodic Table: Version History


Example of how to reference this online database: (Replace year, month day with database access date.)
Alexander Kramida, Karen Olsen, and Yuri Ralchenko, (2019), Periodic Table: Atomic Properties of the Elements (Version 14), NIST SP 966. [Online] Available: http://physics.nist.gov/pt [year, month day]. National Institute of Standards and Technology, Gaithersburg, MD.
Citation Form:
Author/editor (Year), Title (edition). [Type of medium] Available: URL [Access date].
Version 14
July 2019
For the Frequently Used Fundamental Physical Constants section, values have been updated to the 2018 CODATA recommended values. For Technetium and Seaborgium the value of the longest-lived isotope has been updated.
Version 13
July 2018
Ionization Energies were updated for Zr, Pr, Pm, No, and Rf.
Standard Atomic Weights were changed to the Abridged Atomic Weights specified by the Commission on Isotopic Abundances and Atomic Weights (http://www.ciaaw.org/abridged-atomic-weights.htm)
Version 12
February 2017
The value of the electron volt has been rounded to 1.602 177 x 10-19 J.
Version 11
January 2017
Small typographical edits were made.
Version 10
December 2016
For elements 113, 115, 117, and 118 updated the element names and symbols to reflect these newly discovered elements.
Version 9
September 2016

Redesign of the Periodic Table. Several numerical values have been updated. The standard atomic weight of ytterbium has been revised from 173.054 to 173.045. The values of the fundamental physical constants have been updated to the 2014 CODATA recommended values. For elements 103, 107, 108, 109, 111, 113, 115, the mass number of the longest-lived isotope has been updated.

Version 8
January 2015
Added the September 2014 version of the Periodic Table in PDF and TIFF formats. Values in parentheses indicate the mass number of the longest-lived isotope. Values marked with an asterisk: IUPAC conventional atomic weights, standard atomic weights, for these elements are expressed in intervals. See www.iupac.org for explanation and values.
Version 7
May 2013
Added the March 2013 version of the Periodic Table in PDF and TIFF formats.
Version 6.1
September 2010
A PDF version of the Periodic Table without crop marks is now available.
Version 6
September 2010
The online version of the Periodic Table has been updated to the most recent printed version, which is dated September 2010. There was also a September 2009 version. Since version 4, elements have been added such that there are no "missing elements" from 1 to 118. Several official names have been added for high Z elements.
Version 5
November 2005
A home page and version history for the periodic table were designed and a high-resolution TIFF file was made available; fifth & sixth printings of NIST SP 966 occurred in September 2004 & September 2005 with no changes to the data values.
Version 4
September 2003
The ionization energy value was updated for Po; fourth printing of NIST SP 966.
Version 3
September 2002
The ionization energy values were updated for Ne, Pu, and Cm; the atomic weight values were updated for Zn, Kr, and Dy; and the element with atomic number 118 was removed from the periodic table after a retraction by the Lawrence Berkeley National Laboratory; third printing of NIST SP 966.
Version 2
March 2001
The ionization energy values were updated for Y, Sm, Gd, Pt, and Bi; elements with atomic number 114, 116 & 118 were added to the periodic table; second printing of NIST SP 966.
Version 1
April 1999
Periodic Table: Atomic Properties of the Elements available online as a PDF file. All data contained in the periodic table are available from the following three databases:
  1. Ground Levels and Ionization Energies for the Neutral Atoms
  2. Atomic Weights and Isotopic Compositions
  3. Fundamental Physical Constants
Version 1
March 1999
First printing of this NIST handout.

Return to Periodic Table

Created August 19, 2009, Updated August 5, 2019