117 Ts Tennessine 294*
Halogen p-block Period 7 Group 17 Radioactive Synthetic

Tennessine

Ts · Element 117 · Halogens

The second-to-last gap in the seventh period, filled in 2010 with a berkelium target.

STATE AT 20°C Solid
ATOMIC MASS 294 u
ELECTRON CONFIGURATION [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p⁵

Structure

The tennessine atom

Not a diagram of dots on rings — a Monte-Carlo sample of the actual probability density |ψ|² for each occupied subshell. Drag to rotate. Blue and violet mark opposite signs of the wavefunction, which is what makes bonding possible.

Orbital cloud

Measured values

Property sheet

Every bar shows where tennessine sits among all 118 elements for that property.

Physical

Density 7.2 g/cm³~ 44%
Melting point 623 K 32%
Boiling point 883 K 19%
Specific heat
Thermal conductivity

Atomic

Atomic radius 247 pm~ 85%
Covalent radius 165 pm
Van der Waals radius 247 pm~

Electronic

Electronegativity
Ionisation energy 675.4 kJ/mol 48%
Electron affinity 165.9 kJ/mol 87%

Occurrence

Abundance in crust 0 mg/kg 0%

Identity

SymbolTs
Atomic number117
Atomic mass294 u
CategoryHalogen
Blockp
Crystal structureunknown
Oxidation states-1, +1, +3, +5, +7
Discovered2010
Discovered byJINR, Oak Ridge & Livermore

Sources: IUPAC 2021 standard atomic weights · CRC Handbook of Chemistry and Physics · NIST. Values marked ~ are predicted rather than measured.

Size, to scale

How big is a tennessine atom?

Radius 247 pm — that is 0.247 nm, so about 2024 million of them side by side would span a millimetre.

Thermal range

Solid, liquid, gas — and when

Tennessine is liquid over a 260 K window, from 623 K to 883 K.

Where it sits

Position in the table

Tennessine sits in period 7, group 17. Everything in group 17 shares the same outer-electron count, which is why they behave so similarly.

OTHER HALOGENS

All halogens

The story

What tennessine is, and how we found it

The second-to-last gap in the seventh period, filled in 2010 with a berkelium target.

The discovery of tennessine

Joint Institute for Nuclear Research (JINR), Russia & Oak Ridge National Laboratory, USA (2010-2012)

Pinnacle International Collaboration: Tennessine discovery represents a leading achievement in Russian-American scientific cooperation, combining JINR's expertise in superheavy element synthesis with Oak Ridge's unique capabilities in rare actinide target preparation.

Two-Year Intensive Campaign: The tennessine discovery required two years of extraordinarily challenging experimentation from 2010 to 2012, involving the most sophisticated nuclear synthesis techniques ever attempted and achieving success rates of only individual atoms per week.

Oganessian Team Leadership: Led by Yuri Oganessian at the Joint Institute for Nuclear Research in Dubna, Russia, the discovery team overcame seemingly impossible technical challenges to create and identify the heaviest halogen ever synthesized.

Oak Ridge Critical Contributions: Oak Ridge National Laboratory provided the extremely rare berkelium-249 target material essential for tennessine synthesis, representing one of the most challenging target preparation achievements in nuclear physics history.

Significant Technical Innovation: Creating tennessine required developing unprecedented ion beam optimization techniques, ultra-sensitive particle detection systems, and significant data analysis methods that advanced the entire field of superheavy element research.

IUPAC Recognition: The International Union of Pure and Applied Chemistry officially recognized the discovery in 2015, granting naming rights to the discovery team. "Tennessine" honors Tennessee, home state of Oak Ridge National Laboratory.

Historic Scientific Achievement: Tennessine's discovery represented humanity's first successful synthesis of element 117, filling a crucial gap in the periodic table and demonstrating that even the most challenging scientific goals can be achieved through international cooperation.

Applications

What tennessine is used for

Cutting-Edge Nuclear Research

Halogen Chemistry Investigation: Tennessine represents the heaviest known halogen, offering unprecedented opportunities to study how relativistic effects influence halogen chemistry. Theoretical predictions suggest tennessine might exhibit metallic properties despite being in group 17, challenging traditional chemical understanding.

Superheavy Element Synthesis Research: Tennessine creation through berkelium-249 bombardment with calcium-48 provides crucial insights into optimal nuclear reaction conditions for synthesizing the heaviest possible elements, advancing techniques for future periodic table exploration.

Nuclear Stability Studies: As element 117, tennessine occupies a unique position for studying nuclear shell effects and stability patterns in superheavy elements. Its decay characteristics provide valuable data about nuclear forces and stability mechanisms.

Relativistic Quantum Chemistry: Tennessine offers exceptional opportunities to test theoretical models of atomic structure under extreme conditions, particularly calculations predicting how relativistic electron orbital effects influence chemical bonding in superheavy elements.

Advanced Detection Technology: Creating and identifying tennessine requires the most sophisticated particle detection systems available, driving innovation in nuclear instrumentation that benefits multiple scientific fields from medical imaging to space exploration.

International Scientific Collaboration: Tennessine research exemplifies global cooperation in fundamental science, with teams from Russia, the United States, and other nations combining expertise and resources to achieve seemingly impossible scientific goals.

Future Applications Foundation: While currently limited to research, understanding tennessine's properties contributes to the long-term scientific goal of discovering stable superheavy elements that might revolutionize technology in ways currently unimaginable.

Strictly Research Applications

Particle Accelerator Experiments: Tennessine exists only within highly specialized nuclear physics facilities equipped with the most powerful ion accelerators available. Creating tennessine requires months of continuous operation to produce just a few atoms, making each synthesis a remarkable achievement.

Nuclear Reaction Mechanism Studies: Scientists use tennessine synthesis to understand heavy-ion fusion processes and nuclear reaction dynamics at extreme energies, advancing fundamental knowledge of nuclear physics and reaction mechanisms.

Theoretical Chemistry Validation: Tennessine provides experimental data to test quantum mechanical predictions about superheavy element chemistry, particularly theories suggesting unusual chemical behavior for the heaviest halogens.

Advanced Instrumentation Innovation: Tennessine detection drives development of new particle identification systems, timing electronics, and data acquisition methods that benefit broader scientific research including materials science and medical physics.

Scientific Training Excellence: Tennessine experiments provide exceptional training opportunities for nuclear physicists and graduate students, advancing human expertise in superheavy element science and cutting-edge nuclear research techniques.

International Research Coordination: Tennessine studies facilitate collaboration between world-leading nuclear physics laboratories, fostering knowledge sharing and technological advancement across international boundaries.

Where it comes from

Natural occurrence

0 mg/kg of Earth's crust · more abundant than 0% of elements

Completely Artificial Element

No Natural Existence: Tennessine cannot form through any natural nuclear processes occurring anywhere in the universe. Its 117-proton nucleus is far too heavy and unstable to exist in stellar environments, supernovae, neutron star mergers, or any other known astrophysical processes.

Exclusively Laboratory Creation: Every tennessine atom has been artificially created through nuclear fusion reactions in the advanced particle accelerators. The process requires bombarding berkelium-249 targets with calcium-48 ions, achieving success rates of only one or two atoms per week.

Cosmic Impossibility: Even the most extreme cosmic environments lack the precise conditions necessary to create and preserve tennessine nuclei. The element's extremely short half-life ensures that any hypothetically formed tennessine would decay before detection.

Ultra-Specialized Facility Requirement: Tennessine exists only in the world's advanced nuclear physics laboratories, particularly the Joint Institute for Nuclear Research in Russia and Oak Ridge National Laboratory in the United States, representing humanity's ultimate nuclear research capabilities.

Fundamental Nuclear Instability: Tennessine's synthetic nature stems from basic nuclear physics principles. As proton number increases far beyond natural limits, electromagnetic repulsion between protons completely overwhelms the strong nuclear force that holds atomic nuclei together.

Future Production Prospects: While revolutionary accelerator technologies might eventually enhance tennessine synthesis efficiency, the element will always remain artificial due to its inherent nuclear instability and extremely rapid radioactive decay.

Handling

Safety

Tennessine is radioactive. It has no stable isotope — every nucleus decays. Handling requires appropriate shielding and licensing.

Extreme Radioactivity - Ultimate Safety Protocols

Intense Alpha Radiation: Tennessine undergoes extremely rapid alpha decay with half-lives measured in milliseconds, emitting extraordinarily high-energy alpha particles capable of delivering immediately lethal radiation doses. Even single atoms pose extreme hazards.

Maximum Containment Systems: All tennessine research occurs within the most heavily shielded particle accelerator facilities available, featuring multiple redundant containment barriers, sophisticated remote handling systems, and continuous radiation monitoring to protect personnel.

Complex Radioactive Decay: Tennessine decay produces a cascade of radioactive daughter nuclei, each presenting severe radiation risks. Complete decay chain analysis is absolutely essential for proper safety planning and containment system design.

Elite Personnel Only: Tennessine research requires the world's most experienced nuclear physicists with decades of radiation safety training and extensive experience handling the most radiotoxic materials known to science.

Absolute Remote Operation: Tennessine's extreme radioactivity makes any direct handling impossible. All synthesis, detection, and analysis occur through the most sophisticated remote-controlled systems ever developed for nuclear physics research.

Ultimate Environmental Protection: Despite producing only individual atoms, tennessine research facilities maintain the most rigorous environmental monitoring and radioactive waste management protocols available to ensure absolute containment of all radioactive materials.

Quick answers

Tennessine: common questions

What is Tennessine?

Tennessine (symbol Ts) is element 117 on the periodic table, a halogen in period 7, group 17. The second-to-last gap in the seventh period, filled in 2010 with a berkelium target. At room temperature it is a solid, and it is radioactive.

What is the electron configuration of Tennessine?

Tennessine's ground-state electron configuration is [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p⁵, giving 7 occupied shells holding 2, 8, 18, 32, 32, 18, 7 electrons respectively. Its outer shell holds 7 electrons, which is what sets its bonding behaviour.

What are the melting and boiling points of Tennessine?

Tennessine melts at 623 K (349.9 °C) and boils at 883 K (609.9 °C).

What is the atomic mass of Tennessine?

Tennessine has no stable isotope, so it has no standard atomic weight. The figure quoted, 294, is the mass number of its longest-lived known isotope.

How dense is Tennessine?

Tennessine has a density of 7.2 g/cm³. Water is 1.0 g/cm³, so a block of tennessine is about 7.2× heavier.

Who discovered Tennessine, and when?

Tennessine was discovered in 2010 by JINR, Oak Ridge & Livermore. It is named after tennessee.

How common is Tennessine on Earth?

Tennessine does not occur naturally on Earth in any meaningful quantity — it is made in a reactor or an accelerator.

Is Tennessine radioactive?

Yes. Tennessine has no stable isotope — every one of its nuclei decays. It does not occur in usable quantities in nature and must be synthesised.