Method

Datasets and licences

Atomic weights

Published reference values, cited (IUPAC 2021 technical report).

https://doi.org/10.1515/pac-2019-0603

Electron configurations, ionisation energies

NIST Atomic Spectra Database — US Government work, public domain.

https://www.nist.gov/pml/atomic-spectra-database

Physical properties

Published reference values, cited (CRC Handbook, 104th ed.).

https://hbcp.chemnetbase.com/

Nucleosynthetic origin

Published figure, cited (Johnson 2019, Science).

https://doi.org/10.1126/science.aau9540

Indonesian production share

USGS Mineral Commodity Summaries 2024 — US Government work, public domain.

https://doi.org/10.3133/mcs2024

Built from: data/elements/properties.tsv, data/configurations/published.tsv, data/production/usgs.tsv, data/production/tracked.tsv

Citations, per field

• IUPAC Commission on Isotopic Abundances and Atomic Weights, "Atomic weights of the elements 2021", Pure Appl. Chem. 94(5), 573 (2022).
• CRC Handbook of Chemistry and Physics, 104th edition (2023).
• NIST Atomic Spectra Database, Ionization Energies Data (v5.11).
• NIST Atomic Spectra Database ground levels; CRC Handbook 104th ed., "Electron Configuration of Neutral Atoms in the Ground State".
• Slater, J. C., "Atomic Radii in Crystals", J. Chem. Phys. 41, 3199 (1964).
• Johnson, J. A., "Populating the periodic table: Nucleosynthesis of the elements", Science 363, 474 (2019).
• IUPAC element discovery records; Emsley, J., Nature’s Building Blocks, revised ed. (2011).
• U.S. Geological Survey, Mineral Commodity Summaries 2024 (January 2024). Public domain.
• The n+ℓ ordering, generally attributed to E. Madelung, Die mathematischen Hilfsmittel des Physikers, 3rd ed. (1936); also known as the Klechkovsky rule.
• Derived: the number of the seven tracked properties — atomic weight, discovery year, electronegativity, atomic radius, first ionisation energy, melting point, density — for which no published value exists in the sources listed above.

Unknown is not zero

Unknown is not zero. Many properties are simply not known for the superheavy elements — oganesson has no measured electronegativity. Rendering it at the bottom of a colour ramp would state something false, so unknown has one appearance everywhere in this product: a diagonal hatch, never a colour, never a ramp position, never an empty cell. The detail panel says "not known" rather than leaving a blank.

Elements in use since antiquity — carbon, sulfur, iron, copper, silver, tin, antimony, gold, mercury, lead — have no recorded year of discovery. On the discovery lens they are hatched, because a conventional date would invent a precision the record does not have.

Unknown values: 18 electronegativity · 21 density · 10 discovery

The aufbau rule and its exceptions

Electron configurations are stored published values, including the roughly twenty that disagree with the aufbau rule. The rule is implemented separately: it drives the build animation and it is the subject of a test that asserts the disagreement set in both directions. It never supplies a configuration for display.

20 exceptions: 24, 29, 41, 42, 44, 45, 46, 47, 57, 58, 64, 78, 79, 89, 90, 91, 92, 93, 96, 103

NIST Atomic Spectra Database ground levels; CRC Handbook 104th ed., "Electron Configuration of Neutral Atoms in the Ground State".

Group 3 contains scandium, yttrium, lutetium and lawrencium, and the f-block runs 57–70 and 89–102. This follows the IUPAC provisional recommendation and keeps the block widths exactly 2, 6, 10 and 14. Helium is s-block and sits with the noble gases; that is the one position in the table that contradicts its configuration, and it is a chemical convention rather than an error.

The lenses

Exactly one lens is active at any time. Colour is a channel that is swapped, never decoration that accumulates: 118 cells carrying several encodings at once is unreadable, and that is the failure mode this project is built to avoid.

• category
• block
• origin
• production-id
• electronegativity
• atomic-radius
• ionisation-energy
• melting-point
• density
• discovery
• unmeasured

Nucleosynthetic origin is the dominant source, simplified to seven categories. Most elements have more than one production channel, and a single colour cannot say so — the lens names its own limit in the legend.

The views

The table has three views and one of them is showing at a time. The grid colours the cells by the active lens. Topography renders the same lens as height as well as colour, so periodicity reads as waves across the periods rather than as a claim in a caption — it is offered only for continuous lenses, because height cannot order categories without inventing a ranking. The timeline puts the same 118 elements on one axis by year of discovery, still coloured by whichever lens is active.

• grid
• topography
• timeline

Production

Every production figure carries its edition year and its reporting stage. The edition in use is USGS Mineral Commodity Summaries 2024.

Bounds

There is no safety, handling, exposure or emergency-response information anywhere in this product. Hazard classification may appear as a cited fact; guidance is a regulated domain and this is not that tool.

Emission spectra are not in this version. The NIST Atomic Spectra Database is a US Government work and would licence cleanly, but per-element line data is a substantially larger dataset than anything here and it has not been sourced or verified yet.

For a more comprehensive general reference — isotopes, compounds, spectra, orbital viewers — ptable.com is excellent, free and mature. This project is not trying to replace it. It exists for two things ptable does not do: explaining where the shape comes from, and showing Indonesia’s share of world production per element.

https://ptable.com