Ununennium (Uue)
Superactinide標準原子量
データなし電子配置
[Og] 8s¹融点
データなし沸点
データなし密度
3 kg/m³酸化数
++1, ++3電気陰性度（Pauling）
0.86第1イオン化エネルギー
463.1 eV発見年
データなし原子半径
240 pmUnunennium is the temporary IUPAC name for element 119, an undiscovered superheavy element placed below francium in group 1. All of its properties are predicted. It is expected to have an outer 8s electron and broadly alkali-metal-like chemistry, but strong relativistic effects may make it less simple than a direct extrapolation from cesium or francium. No isotope has been confirmed.
This element has not been synthesized or experimentally confirmed. All listed physicochemical properties are calculated, extrapolated, or model-dependent.
No macroscopic sample of ununennium exists, so its appearance is unknown. It is usually predicted to be a metallic solid under ordinary conditions, but color, luster, density, melting point, and other bulk properties have not been measured.
Ununennium has no confirmed practical, industrial, medical, or commercial use. If produced, it would be made atom by atom for nuclear and chemical research, chiefly to test models of superheavy nuclei, decay chains, and relativistic effects in the heaviest group 1 element. Any chemical study would probably involve single atoms or very small numbers of atoms and short observation times.
No compound of ununennium has been synthesized or characterized. Calculations predict that the +1 oxidation state and the Uue⁺ ion would be the most accessible, as in lighter alkali metals. Representative species considered in theoretical work include ununennium fluoride (UueF), ununennium chloride (UueCl), and ununennium hydroxide (UueOH). Relativistic stabilization of the 8s electron may alter bond strengths and volatility relative to simple periodic trends.
The safety properties of ununennium are not experimentally known. Any atoms produced would be radioactive, and isotope-specific half-lives and decay modes would control the hazard. In practice, risks would arise mainly from accelerator operation, radioactive targets, recoil products, and decay radiation, not from chemical toxicity of a bulk element. No ordinary exposure scenario exists.
Ununennium has no confirmed natural occurrence and no known environmental cycle. Because no isotope has been observed, its environmental mobility, speciation, and ecological effects are unmeasured. If atoms were produced in a laboratory, their quantities would be far too small for environmental behavior to be studied directly, and rapid radioactive decay is expected to dominate their fate.
Ununennium has no commodity market, commercial supply chain, or recoverable source. Production, if achieved, would require a heavy-ion accelerator, an intense beam, and a rare heavy actinide target, followed by atom-at-a-time detection. The limiting factors are target availability, beam time, very low reaction probabilities, and short-lived products. Economic discussion is therefore about research capability rather than demand, substitution, or recycling.
No confirmed ununennium has been detected on Earth or in extraterrestrial material. Superheavy nuclei near this region may be formed transiently in extreme nucleosynthesis environments, but any such atoms are expected to decay rapidly unless an unusually long-lived isotope exists. The proposed island of stability remains a theoretical motivation for searches.
- Ununennium is a systematic temporary name meaning one-one-nine.
- It would begin the eighth period of the periodic table if confirmed.
- No isotope of ununennium has yet been accepted as discovered.
- Its chemistry is inferred from theory and periodic trends, not experiments.
- Detection would rely on nuclear decay signatures rather than a visible sample.
- Relativistic effects are expected to be important for its 8s electron.
画像
性質
物理的性質
- 原子半径（経験値）
- 240 pm 全元素の原子半径（経験値）を比較 →
- 共有結合半径
- 272 pm 全元素の共有結合半径を比較 →
- 密度
- 3 kg/m³ 全元素の密度を比較 →
- 結晶構造
- 体心立方構造 全元素の結晶構造を比較 →
化学的性質
- 電気陰性度（Pauling）
- 0.86 全元素の電気陰性度（Pauling）を比較 →
- 電子親和力
- 0.25 eV
- 第1イオン化エネルギー
- 463.1 eV 全元素の第1イオン化エネルギーを比較 →
- 酸化数
- ++1, ++3 全元素の酸化数を比較 →
- 電子配置
- [Og] 8s¹
熱力学的性質
データなし
原子核
- 陽子数
- 119 全元素の陽子数を比較 →
- 既知の同位体
- 0 全元素の既知の同位体を比較 →
- 安定同位体
- 0 全元素の安定同位体を比較 →
- 天然での存在
- 未観測
存在度
データなし
安全性
- 放射性
- はい
結晶構造
データなし
電子構造
- 各電子殻の電子数
- 2, 8, 18, 32, 32, 18, 8, 1 全元素の各電子殻の電子数を比較 →
識別子
- CAS登録番号
- 54846-86-5 全元素のCAS登録番号を比較 →
電子配置 予測値
——このイオンの電子配置データはありません。
原子モデル
同位体によって中性子数、質量、安定性は変わりますが、中性原子の電子配置は変わりません。
データなし
模式的な原子モデルです。実際の縮尺とは異なります。
原子の指紋
発光／吸収スペクトル
同位体分布
安定同位体はありません。
| 質量数 | 原子質量（u） | 天然存在比 | 半減期 |
|---|
相／状態
相・状態のデータはありません
データなし
相・状態のデータはありません