Tennessine

HALOGEN · GROUP 17 · PERIOD 7
117
Ts
Tennessine
294

Atomic Data

Atomic Number117
SymbolTs
Atomic Weight294 u
Density (STP)N/A
Melting PointN/A °C (None K)
Boiling PointN/A °C (None K)
Electronegativity:
Electron Config.1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 5f14 6s2 6p6 6d10 7s2 7p5
Oxidation States−1, +1, +3, +5
Phase at STPSolid
CategoryHalogen
Period / Group7 / 17
CAS Number87658-56-8

Electron Configuration

[Rn] 5f14 6d10 7s2 7p5

Shell n Subshell Electrons Cumulative
K11s22
L22s24
L22p610
M33s212
M33p618
M33d1028
N44s230
N44p636
N44d1046
N44f1460
O55s262
O55p668
O55d1078
O55f1492
P66s294
P66p6100
P66d10110
Q77s2112
Q77p5117
Total 117 117

Isotopes of Tennessine

Tennessine is monoisotopic: ²⁹⁴Ts is its only naturally occurring stable isotope, accounting for 100% of all natural Tennessine.

Isotope Symbol Protons Neutrons Abundance Stability
Tennessine-294²⁹⁴Ts117177traceStable

Abundance & Occurrence

Tennessine is present in Earth's crust at approximately trace amounts by mass and at approximately trace amounts by mass throughout the universe.

Earth's Crust (ppm by mass)

Tennessine
None ppm
Silicon (ref.)
277,000 ppm
Oxygen (ref.)
461,000 ppm

Universe (ppm by mass)

Tennessine
None ppm
Helium (ref.)
230,000 ppm
Hydrogen (ref.)
739,000 ppm

Discovery & History

2010
Yuri Oganessian et al. (JINR, Dubna / Oak Ridge / Vanderbilt / Lawrence Livermore): Tennessine was synthesised by bombarding berkelium-249 targets: produced at Oak Ridge National Laboratory after 250 days of reactor irradiation: with calcium-48 ions at Dubna, producing six atoms of Ts-293 and Ts-294.
2016
IUPAC: IUPAC named the element tennessine after the state of Tennessee, USA, honouring the contributions of Oak Ridge National Laboratory, Vanderbilt University, and the University of Tennessee to superheavy element research.
2016
GSI confirmation team: An independent confirmation experiment at GSI provided the replication needed for IUPAC's formal acceptance; tennessine is expected to be a halogen homologue but relativistic effects may give it significantly different chemistry from iodine or astatine.

Safety & Handling

  • Alpha radiation and very short half-life: Tennessine isotopes are alpha emitters; Ts-294 (t½ = 51 ms) and Ts-293 (t½ = 22 ms) decay almost instantaneously, making chemical characterisation essentially impossible with current techniques.
  • No practical bulk hazard: Only a handful of tennessine atoms have ever been produced; there is no macroscopic radiological or chemical hazard.
  • Berkelium target radiation: Ts synthesis requires Bk-249 targets produced only at Oak Ridge after 250+ days of reactor irradiation; the intense radioactivity of the Bk-249 target is the principal radiological hazard of the production chain.
  • Regulatory controls: All tennessine research is conducted under US Department of Energy and Russian Rosatom nuclear regulatory frameworks, with full radiation protection and international safeguards.

Real-World Uses

  • Superheavy halogen chemistry predictions: Tennessine (Ts-293, Ts-294) is in Group 17 (halogens); relativistic calculations predict it will not form negative ions as readily as lighter halogens and may behave more like a metal than a halogen, representing a potential breakdown of Group 17 periodic trends at the heaviest elements.
  • Decay chain bridging: The alpha-decay chain of tennessine passes through moscovium (Z=115), nihonium (Z=113), roentgenium (Z=111), and meitnerium (Z=109), providing identification links for all these intermediate species and contributing to the systematic characterisation of the superheavy element region.
  • No commercial applications: Tennessine is produced a few atoms at a time using the scarce Bk-249 target; its most stable known isotope (Ts-294) has a half-life of about 51 milliseconds, making no practical application conceivable.

Downloadable Resources

Free periodic table reference sheets for classrooms, study sessions, and laboratory use.

Frequently Asked Questions

Has tennessine ever been used for anything?

No. Tennessine has no practical applications. Its most stable isotope (Ts-294) has a half-life of about 51 milliseconds. It is produced only a handful of atoms at a time in particle accelerators and is studied purely for fundamental nuclear research. The synthesis of tennessine was a landmark collaborative effort requiring berkelium-249 targets produced at Oak Ridge National Laboratory.

How many atoms of tennessine have been made?

Tennessine was first synthesised in 2010 at JINR in Dubna, Russia, by bombarding berkelium-249 targets with calcium-48 ions. Only about 5 atoms were produced in the initial experiments over several months of bombardment. The 22-milligram berkelium target required 250 days of reactor irradiation to produce. Since then, a total of roughly a dozen tennessine atoms have been produced.

Is tennessine radioactive?

Yes, all isotopes of tennessine are radioactive. The most stable known, Ts-294, has a half-life of about 51 milliseconds. Ts-293 has a half-life of about 22 milliseconds. Both decay by alpha emission. All tennessine atoms decay almost immediately after production.

How did tennessine get its name?

Tennessine was named after the state of Tennessee, home to Oak Ridge National Laboratory (which produced the berkelium-249 target), Vanderbilt University, and the University of Tennessee: all of which contributed to the research. The name was approved by IUPAC in 2016. Tennessine is only the second element named after a US state, the other being californium (element 98).