scholarly journals Isotope-abundance variations and atomic weights of selected elements: 2016 (IUPAC Technical Report)

2016 ◽  
Vol 88 (12) ◽  
pp. 1203-1224 ◽  
Author(s):  
Tyler B. Coplen ◽  
Yesha Shrestha
Keyword(s):  
Chemical Elements ◽  
Radioactive Decay ◽  
Atomic Weight ◽  
Upper And Lower Bounds ◽  
Chemical Fractionation ◽  
Lower And Upper Bounds ◽  
Technical Report ◽  
Isotopic Abundances ◽  
Physical And Chemical ◽  
Boron Carbon

AbstractThere are 63 chemical elements that have two or more isotopes that are used to determine their standard atomic weights. The isotopic abundances and atomic weights of these elements can vary in normal materials due to physical and chemical fractionation processes (not due to radioactive decay). These variations are well known for 12 elements (hydrogen, lithium, boron, carbon, nitrogen, oxygen, magnesium, silicon, sulfur, chlorine, bromine, and thallium), and the standard atomic weight of each of these elements is given by IUPAC as an interval with lower and upper bounds. Graphical plots of selected materials and compounds of each of these elements have been published previously. Herein and at the URL http://dx.doi.org/10.5066/F7GF0RN2, we provide isotopic abundances, isotope-delta values, and atomic weights for each of the upper and lower bounds of these materials and compounds.

Isotope-abundance variations of selected elements (IUPAC Technical Report)

2002 ◽  
Vol 74 (10) ◽  
pp. 1987-2017 ◽  
Author(s):  
Tyler B. Coplen ◽  
John Karl Böhlke ◽  
P. De Bièvre ◽  
T. Ding ◽  
N. E. Holden ◽  
...  
Keyword(s):  
Chemical Elements ◽  
Radioactive Decay ◽  
Atomic Weight ◽  
Chemical Fractionation ◽  
Isotope Abundance ◽  
Isotopic Compositions ◽  
Technical Report ◽  
Isotopic Abundances ◽  
Calcium Iron ◽  
Physical And Chemical

Documented variations in the isotopic compositions of some chemical elements are responsible for expanded uncertainties in the standard atomic weights published by the Commission on Atomic Weights and Isotopic Abundances of the International Union of Pure and Applied Chemistry. This report summarizes reported variations in the isotopic compositions of 20 elements that are due to physical and chemical fractionation processes (not due to radioactive decay) and their effects on the standard atomic-weight uncertainties. For 11 of those elements (hydrogen, lithium, boron, carbon, nitrogen, oxygen, silicon, sulfur, chlorine, copper, and selenium), standard atomic-weight uncertainties have been assigned values that are substantially larger than analytical uncertainties because of common isotope-abundance variations in materials of natural terrestrial origin. For 2 elements (chromium and thallium), recently reported isotope-abundance variations potentially are large enough to result in future expansion of their atomic-weight uncertainties. For 7 elements (magnesium, calcium, iron, zinc, molybdenum, palladium, and tellurium), documented isotope variations in materials of natural ter- restrial origin are too small to have a significant effect on their standard atomic-weight uncertainties. This compilation indicates the extent to which the atomic weight of an element in a given material may differ from the standard atomic weight of the element. For most elements given above, data are graphically illustrated by a diagram in which the materials are specified in the ordinate and the compositional ranges are plotted along the abscissa in scales of (1) atomic weight, (2) mole fraction of a selected isotope, and (3) delta value of a selected isotope ratio.

scholarly journals Interpreting and propagating the uncertainty of the standard atomic weights (IUPAC Technical Report)

2018 ◽  
Vol 90 (2) ◽  
pp. 395-424 ◽  
Author(s):  
Antonio Possolo ◽  
Adriaan M. H. van der Veen ◽  
Juris Meija ◽  
D. Brynn Hibbert
Keyword(s):  
Probability Distribution ◽  
Isotopic Composition ◽  
Probability Distributions ◽  
Atomic Weight ◽  
Relative Molecular Mass ◽  
Detailed Knowledge ◽  
Technical Report ◽  
Other Information ◽  
Isotopic Abundances ◽  
Molecular Masses

AbstractIn 2009, the Commission on Isotopic Abundances and Atomic Weights (CIAAW) of the International Union of Pure and Applied Chemistry (IUPAC) introduced the interval notation to express the standard atomic weights of elements whose isotopic composition varies significantly in nature. However, it has become apparent that additional guidance would be helpful on how representative values should be derived from these intervals, and on how the associated uncertainty should be characterized and propagated to cognate quantities, such as relative molecular masses. The assignment of suitable probability distributions to the atomic weight intervals is consistent with the CIAAW’s goal of emphasizing the variability of the atomic weight values in nature. These distributions, however, are not intended to reflect the natural variability of the abundances of the different isotopes in the earth’s crust or in any other environment. Rather, they convey states of knowledge about the elemental composition of “normal” materials generally, or about specific classes of such materials. In the absence of detailed knowledge about the isotopic composition of a material, or when such details may safely be ignored, the probability distribution assigned to the standard atomic weight intervals may be taken as rectangular (or, uniform). This modeling choice is a reasonable and convenient default choice when a representative value of the atomic weight, and associated uncertainty, are needed in calculations involving atomic and relative molecular masses. When information about the provenance of the material, or other information about the isotopic composition needs to be taken into account, then this distribution may be non-uniform. We present several examples of how the probability distribution of an atomic weight or relative molecular mass may be characterized, and also how it may be used to evaluate the associated uncertainty.

scholarly journals Isotopic compositions of the elements 2009 (IUPAC Technical Report)

2011 ◽  
Vol 83 (2) ◽  
pp. 397-410 ◽  
Author(s):  
Michael Berglund ◽  
Michael E. Wieser
Keyword(s):  
Mass Spectrometry ◽  
Isotope Ratio ◽  
Critical Evaluation ◽  
Isotope Ratio Mass Spectrometry ◽  
Atomic Weight ◽  
Single Sample ◽  
International Union ◽  
Isotopic Compositions ◽  
Technical Report ◽  
Isotopic Abundances

The Commission on Isotopic Abundances and Atomic Weights (CIAAW) of the International Union of Pure and Applied Chemistry (IUPAC) completed its last update of the isotopic compositions of the elements as determined by isotope-ratio mass spectrometry in 2009. That update involved a critical evaluation of the published literature and forms the basis of the table of the isotopic compositions of the elements (TICE) presented here. For each element, TICE includes evaluated data from the “best measurement” of the isotope abundances in a single sample, along with a set of representative isotope abundances and uncertainties that accommodate known variations in normal terrestrial materials. The representative isotope abundances and uncertainties generally are consistent with the standard atomic weight of the element Ar(E) and its uncertainty U[Ar(E)] recommended by CIAAW in 2007.

scholarly journals Review of footnotes and annotations to the 1949–2013 tables of standard atomic weights and tables of isotopic compositions of the elements (IUPAC Technical Report)

2016 ◽  
Vol 88 (7) ◽  
pp. 689-699 ◽  
Author(s):  
Tyler B. Coplen ◽  
Norman E. Holden
Keyword(s):  
Isotopic Fractionation ◽  
Numerical Data ◽  
Atomic Weight ◽  
Current Standard ◽  
Additional Information ◽  
Isotopic Compositions ◽  
Technical Report ◽  
Isotopic Abundances ◽  
Terrestrial Material ◽  
A Current

Abstract The Commission on Isotopic Abundances and Atomic Weights uses annotations given in footnotes that are an integral part of the Tables of Standard Atomic Weights to alert users to the possibilities of quite extraordinary occurrences, as well as sources with abnormal atomic-weight values outside an otherwise acceptable range. The basic need for footnotes to the Standard Atomic Weights Table and equivalent annotations to the Table of Isotopic Compositions of the Elements arises from the necessity to provide users with information that is relevant to one or more elements, but that cannot be provided using numerical data in columns. Any desire to increase additional information conveyed by annotations to these Tables is tempered by the need to preserve a compact format and a style that can alert users, who would not be inclined to consult either the last full element-by-element review or the full text of a current Standard Atomic Weights of the Elements report. Since 1989, the footnotes of the Tables of Standard Atomic Weights and the annotations in column 5 of the Table of Isotopic Compositions of the Elements have been harmonized by use of three lowercase footnotes, “g”, “m”, and “r”, that signify geologically exceptionally specimens (“g”), modified isotopic compositions in material subjected to undisclosed or inadvertent isotopic fractionation (“m”), and the range in isotopic composition of normal terrestrial material prevents more precise atomic-weight value being given (“r”). As some elements are assigned intervals for their standard atomic-weight values (applies to 12 elements since 2009), footnotes “g” and “r” are no longer needed for these elements.

scholarly journals Atomic weights of the elements 2013 (IUPAC Technical Report)

2016 ◽  
Vol 88 (3) ◽  
pp. 265-291 ◽  
Author(s):  
Juris Meija ◽  
Tyler B. Coplen ◽  
Michael Berglund ◽  
Willi A. Brand ◽  
Paul De Bièvre ◽  
...  
Keyword(s):  
Isotope Ratio ◽  
Atomic Weight ◽  
Atomic Mass ◽  
Uranium Isotope ◽  
List Type ◽  
Technical Report ◽  
Isotopic Abundances ◽  
Standard Value

AbstractThe biennial review of atomic-weight determinations and other cognate data has resulted in changes for the standard atomic weights of 19 elements. The standard atomic weights of four elements have been revised based on recent determinations of isotopic abundances in natural terrestrial materials: cadmium to 112.414(4) from 112.411(8),molybdenum to 95.95(1) from 95.96(2),selenium to 78.971(8) from 78.96(3), andthorium to 232.0377(4) from 232.038 06(2).The Commission on Isotopic Abundances and Atomic Weights (ciaaw.org) also revised the standard atomic weights of fifteen elements based on the 2012 Atomic Mass Evaluation: aluminium (aluminum) to 26.981 5385(7) from 26.981 5386(8),arsenic to 74.921 595(6) from 74.921 60(2),beryllium to 9.012 1831(5) from 9.012 182(3),caesium (cesium) to 132.905 451 96(6) from 132.905 4519(2),cobalt to 58.933 194(4) from 58.933 195(5),fluorine to 18.998 403 163(6) from 18.998 4032(5),gold to 196.966 569(5) from 196.966 569(4),holmium to 164.930 33(2) from 164.930 32(2),manganese to 54.938 044(3) from 54.938 045(5),niobium to 92.906 37(2) from 92.906 38(2),phosphorus to 30.973 761 998(5) from 30.973 762(2),praseodymium to 140.907 66(2) from 140.907 65(2),scandium to 44.955 908(5) from 44.955 912(6),thulium to 168.934 22(2) from 168.934 21(2), andyttrium to 88.905 84(2) from 88.905 85(2).The Commission also recommends the standard value for the natural terrestrial uranium isotope ratio, N(238U)/N(235U)=137.8(1).

scholarly journals IUPAC Periodic Table of the Elements and Isotopes (IPTEI) for the Education Community (IUPAC Technical Report)

2018 ◽  
Vol 90 (12) ◽  
pp. 1833-2092 ◽  
Author(s):  
Norman E. Holden ◽  
Tyler B. Coplen ◽  
John K. Böhlke ◽  
Lauren V. Tarbox ◽  
Jacqueline Benefield ◽  
...  
Keyword(s):  
Periodic Table ◽  
Environmental Science ◽  
Chemical Elements ◽  
Atomic Weight ◽  
Radioactive Isotopes ◽  
Practical Applications ◽  
Education Community ◽  
Technical Report ◽  
Color Scheme ◽  
Isotopic Measurements

AbstractThe IUPAC (International Union of Pure and Applied Chemistry) Periodic Table of the Elements and Isotopes (IPTEI) was created to familiarize students, teachers, and non-professionals with the existence and importance of isotopes of the chemical elements. The IPTEI is modeled on the familiar Periodic Table of the Chemical Elements. The IPTEI is intended to hang on the walls of chemistry laboratories and classrooms. Each cell of the IPTEI provides the chemical name, symbol, atomic number, and standard atomic weight of an element. Color-coded pie charts in each element cell display the stable isotopes and the relatively long-lived radioactive isotopes having characteristic terrestrial isotopic compositions that determine the standard atomic weight of each element. The background color scheme of cells categorizes the 118 elements into four groups: (1) white indicates the element has no standard atomic weight, (2) blue indicates the element has only one isotope that is used to determine its standard atomic weight, which is given as a single value with an uncertainty, (3) yellow indicates the element has two or more isotopes that are used to determine its standard atomic weight, which is given as a single value with an uncertainty, and (4) pink indicates the element has a well-documented variation in its atomic weight, and the standard atomic weight is expressed as an interval. An element-by-element review accompanies the IPTEI and includes a chart of all known stable and radioactive isotopes for each element. Practical applications of isotopic measurements and technologies are included for the following fields: forensic science, geochronology, Earth-system sciences, environmental science, and human health sciences, including medical diagnosis and treatment.

Lead and oxygen isotopes in ancient objects

1970 ◽  
Vol 269 (1193) ◽  
pp. 143-164 ◽  
Keyword(s):  
Lead Isotopes ◽  
Radioactive Decay ◽  
Chemical Fractionation ◽  
The Past ◽  
The Earth ◽  
Dating Method ◽  
Physical And Chemical ◽  
Isotopic Variations ◽  
Radioactive Species ◽  
Archaeological Objects

During the past few years most archaeologists and museum curators have become familiar with the term isotope . Isotopes are atoms of the same chemical element which differ slightly from one another in mass. For instance, there are four stable isotopes of lead, 204 Pb, 206 Pb, 207 Pb and 208 Pb, having, respectively, approximate masses of 204, 206, 207 and 208 atomic mass units; and there are three isotopes of oxygen, 16 O, 17 O and 18 O, having masses of 16, 17 and 18. The isotopic composition of most elements is uniform throughout nature. That is to say, occurrences of a particular element in different places or in different chemical forms usually contain the same relative proportions of that element’s isotopes. There are, however, a few notable exceptions, and wherever they occur they are invariably of interest to the scientist. The example most familiar to the archaeologist is the variation in the proportion of 14 C in the carbon present in archaeological objects. This variation constitutes the basis of radiocarbon dating, the discovery and remarkable advances of which are being commemorated at this Symposium. In this paper we shall deal with two other elements, lead and oxygen, whose isotopic compositions vary in natural occurrences due to rather well defined mechanisms. Unlike the 12 C— 14 C relationship, which involves the decay of a radioactive species and leads directly to a dating method, the research reported here with lead and oxygen does not involve radioactive decay in the same way, and neither investigation at this stage is aimed towards developing a direct dating method for archaeological finds. With lead, the isotopic variations observed are associated with differences in the geological ages and geochemical origins of lead deposits. (The differences arise because three of the four lead isotopes are continually produced within the earth by radioactive decay of uranium and thorium.) In the case of oxygen, physical and chemical fractionation processes are responsible for the isotopic variations.

Atomic weights of the elements 1999 (IUPAC Technical Report)

2001 ◽  
Vol 73 (4) ◽  
pp. 667-683 ◽  
Author(s):  
Tyler B. Coplen
Keyword(s):  
Isotopic Composition ◽  
Scientific Community ◽  
Atomic Weight ◽  
Atomic Mass ◽  
Isotopic Abundance ◽  
Technical Report ◽  
Relative Atomic Mass ◽  
Isotopic Abundances

The biennial review of atomic-weight, Ar(E), determinations and other cognate data have resulted in changes for the standard atomic weights of the following elements: elementFromTonitrogen14.006 74 ± 0.000 0714.0067 ± 0.0002 sulfur32.066 ± 0.00632.065 ± 0.005 chlorine35.4527 ± 0.000935.453 ± 0.002germanium72.61 ± 0.0272.64 ± 0.01 xenon131.29 ± 0.02131.293 ± 0.006 erbium167.26 ± 0.03167.259 ± 0.003 uranium238.0289 ± 0.0001238.028 91 ± 0.000 03 Presented are updated tables of the standard atomic weights and their uncertainties estimated by combining experimental uncertainties and terrestrial variabilities. In addition, this report again contains an updated table of relative atomic-mass values and half-lives of selected radioisotopes. Changes in the evaluated isotopic abundance values from those published in 1997 are so minor that an updated list will not be published for the year 1999.Many elements have a different isotopic composition in some nonterrestrial materials. Some recent data on parent nuclides that might affect isotopic abundances or atomic-weight values are included in this report for the information of the interested scientific community.

scholarly journals Standard Atomic Weight of Lead Revised

2021 ◽  
Vol 43 (3) ◽  
pp. 30-30
Keyword(s):  
Isotopic Composition ◽  
Atomic Weight ◽  
Atomic Mass ◽  
Lead Isotopic Composition ◽  
Technical Report ◽  
Relative Atomic Mass ◽  
Isotopic Abundances ◽  
Iupac Commission

Abstract Following the recent publication of the IUPAC Technical Report on the variation of lead isotopic composition and atomic weight in terrestrial materials [1], the IUPAC Commission on Isotopic Abundances and Atomic Weights (CIAAW) is recommending changes to the standard atomic weight (i.e. relative atomic mass) of lead:

scholarly journals Variation of lead isotopic composition and atomic weight in terrestrial materials (IUPAC Technical Report)

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Xiang-Kun Zhu ◽  
Jacqueline Benefield ◽  
Tyler B. Coplen ◽  
Zhaofu Gao ◽  
Norman E. Holden
Keyword(s):  
Isotopic Composition ◽  
Radioactive Decay ◽  
Isotope Ratios ◽  
Atomic Weight ◽  
High Grade ◽  
A Value ◽  
Metamorphic Terrain ◽  
Phosphate Mineral ◽  
Technical Report ◽  
North Western

AbstractThe isotopic composition and atomic weight of lead are variable in terrestrial materials because its three heaviest stable isotopes are stable end-products of the radioactive decay of uranium (238U to 206Pb; 235U to 207Pb) and thorium (232Th to 208Pb). The lightest stable isotope, 204Pb, is primordial. These variations in isotope ratios and atomic weights provide useful information in many areas of science, including geochronology, archaeology, environmental studies, and forensic science. While elemental lead can serve as an abundant and homogeneous isotopic reference, deviations from the isotope ratios in other lead occurrences limit the accuracy with which a standard atomic weight can be given for lead. In a comprehensive review of several hundred publications and analyses of more than 8000 samples, published isotope data indicate that the lowest reported lead atomic weight of a normal terrestrial materials is 206.1462 ± 0.0028 (k = 2), determined for a growth of the phosphate mineral monazite around a garnet relic from an Archean high-grade metamorphic terrain in north-western Scotland, which contains mostly 206Pb and almost no 204Pb. The highest published lead atomic weight is 207.9351 ± 0.0005 (k = 2) for monazite from a micro-inclusion in a garnet relic, also from a high-grade metamorphic terrain in north-western Scotland, which contains almost pure radiogenic 208Pb. When expressed as an interval, the lead atomic weight is [206.14, 207.94]. It is proposed that a value of 207.2 be adopted for the single lead atomic-weight value for education, commerce, and industry, corresponding to previously published conventional atomic-weight values.

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