// MATTER · ELEMENT 111 / 118atoms.no/elements
Rg111
Roentgenium
Rg·Z 111·Unknown·282·⭕ 10B · D Major
▸ The reading
interpretive · artRoentgenium honours Wilhelm Röntgen, whose X-rays remain the most direct way to fix an atom's element number — element 111 is named for that tool, though Rg itself was read from its decay chain. Predicted to sit in gold's group, unconfirmed. The discoverer of the light that reads the table, written into it.
The science below is cited as science; the symbolic layers are flagged as interactive art.
⚜ Periodic Frequency
10BD Major
a seat struck in brass — testimony, not prediction
the seat has its own room on ⭕ THE OVAL TABLE — tap the code
▸ The lenses
▸ Discovery
Sigurd Hofmann + colleagues at GSI Darmstadt · Germany · 1994
▸ Stellar origin
Human-madeGroup-11 transactinide. Longest-lived isotope ²⁸²Rg has a half-life of about two minutes.
▸ Reactivity
Predicted to be a gold-group transition metalRelativistic effects in row 7 are predicted to make Rg break gold's pattern, with a calculated 6d⁹7s² ground state where Cu, Ag and Au are all d¹⁰s¹ — relativistic contraction may stabilize unusual oxidation states.
▸ Applications
- Heavy-element synthesis research
- (No commercial applications)
- (No practical bulk uses)
- (No medical uses)
▸ Curiosity
Named for Wilhelm Conrad Röntgen, who discovered X-rays in 1895 — the technique Moseley used in 1913 to fix atomic number by spectrum — the measure the periodic table is still ordered by.
▸ Related readings
a resonance drawn between readings — not a claim that they share an origin.
Group 11AuGold
Period 7DsDarmstadtiumCnCopernicium
d-blockDsDarmstadtiumCnCopernicium
Adjacent ZDsDarmstadtiumCnCopernicium