Unbioctium (Ubo)
SuperactinideStandard Atomic Weight
N/AElectron configuration
[Og] 5g⁸ 8s²Melting point
N/ABoiling point
N/ADensity
N/AOxidation states
N/AElectronegativity (Pauling)
N/AIonization energy (1st)
N/ADiscovery year
N/AAtomic radius
N/AUnbioctium is the temporary systematic name for element 128, a predicted superheavy element that has not been synthesized or observed. It would lie in the superactinide region of extended periodic tables. Its chemical character is unknown, because relativistic effects and the close spacing of 5g, 6f, 7d, and 8p levels make simple extrapolation unreliable. Any discussion of its properties is theoretical.
This element has not been synthesized or experimentally confirmed. All listed physicochemical properties are calculated, extrapolated, or model-dependent.
No macroscopic sample of unbioctium exists, and even single atoms have not been reported. Its color, density, melting point, crystal structure, and other bulk physical properties are therefore unknown. Published descriptions of appearance would be predictions only.
Unbioctium has no confirmed practical, commercial, medical, or industrial use. If it is ever produced, the initial use would be limited to nuclear-physics research, such as identifying decay chains, measuring half-lives, and testing models of superheavy nuclear stability. Chemical study would require atom-at-a-time methods and would depend on isotopes surviving long enough for separation or gas-phase experiments.
No compound of unbioctium has been made or detected. Its possible chemistry is inferred only from electronic-structure calculations for superheavy atoms. Models generally expect positive oxidation states if chemical reactions can be observed, but the likely range is not securely established. Relativistic orbital contraction and expansion may alter trends relative to lighter actinides and transactinides, so predicted fluorides, oxides, or coordination species should be treated as hypothetical rather than characterized substances.
The safety properties of unbioctium are not experimentally known. Any isotope that could be produced would almost certainly be radioactive and made in extremely small numbers of atoms. The practical hazard in a synthesis experiment would come mainly from accelerator operations, target materials, recoil separators, and decay radiation from short-lived products. Chemical toxicity cannot be assessed from observation.
There is no confirmed natural occurrence of unbioctium and no evidence for an environmental cycle. Any atoms produced in a laboratory would decay before they could disperse as a persistent contaminant. Environmental behavior such as solubility, adsorption, bioaccumulation, or mobility is therefore unmeasured and can only be modeled from uncertain chemical analogies.
Unbioctium has no commodity market, no recoverable source, and no supply chain. Production, if achieved, would require heavy-ion fusion experiments using specialized accelerators, rare targets, and sensitive detection systems. Yields would be expected to be atom-at-a-time, not material quantities. Economic discussion is therefore limited to the cost and feasibility of research campaigns, target preparation, beam time, and detector operation rather than trade in the element itself.
Unbioctium has not been identified in nature, meteorites, stellar spectra, or cosmic-ray material. Nuclei with this charge would be far beyond the long-lived primordial nuclides known on Earth. Astrophysical nucleosynthesis might transiently pass through very heavy nuclei in extreme neutron-rich events, but survival of element 128 to observable times is unconfirmed.
- Unbioctium is a systematic placeholder name, not a discovery name.
- No isotope of element 128 has been accepted as synthesized.
- Predicted chemistry is especially uncertain because several valence shells may be close in energy.
- A nucleus with 128 protons and 184 neutrons would have mass number 312.
- Any first identification would likely rely on correlated radioactive decays, not weighing a sample.
Images
Properties
Physical
N/A
Chemical
- Electron affinity
- 0.5 eV
- Electron configuration
- [Og] 5g⁸ 8s²
Thermodynamic
N/A
Nuclear
- Protons
- 128 Compare Protons of all elements →
- Known isotopes
- 0 Compare Known isotopes of all elements →
- Stable isotopes
- 0 Compare Stable isotopes of all elements →
- Natural occurrence
- Not observed
Abundance
N/A
Safety
- Radioactive
- Yes
Crystal Structure
N/A
Electronic Structure
- Electrons per shell
- 2, 8, 18, 32, 40, 18, 8, 2 Compare Electrons per shell of all elements →
Identifiers
- CAS number
- 54576-79-3 Compare CAS number of all elements →
Electron Configuration Predicted
——Electron configuration data not available for this ion.
Atomic model
Isotopes change neutron count, mass, and stability — not the electron configuration of a neutral atom.
N/A
Schematic atomic model, not to scale.
Atomic Fingerprint
Emission / Absorption Spectrum
Isotope Distribution
No stable isotopes.
| Mass number | Atomic mass (u) | Natural abundance | Half-life |
|---|
Phase / State
Phase/state data not available
N/A
Phase/state data not available