Flerovium (Fl)
post-transition-metalExpected to be a Solid
標準原子量
[289]電子配置
[Rn] 7s2 7p2 5f14 6d10 (予測値)融点
データなし沸点
-63.15 °C密度
9928 kg/m³酸化数
0, +1, +2, +4, +6電気陰性度（Pauling）
データなし第1イオン化エネルギー
データなし発見年
1998原子半径
180 pm詳細
Flerovium is a synthetic superheavy element in group 14, below lead. It has been made only atom by atom in heavy-ion fusion reactions, and all confirmed isotopes are radioactive and short-lived. Its chemistry is dominated by strong relativistic effects, so it is not expected to behave as a simple heavier analogue of lead. Experimental chemical information is sparse, but it points to unusually weak metallic bonding and high volatility for a group 14 element.
Flerovium does not occur naturally in the Earth’s crust. Flerovium was named for the Flerov Laboratory for Nuclear Reactions of the Joint Institute for Nuclear Research (JIRN). In 1999, a collaboration of scientists from the Joint Institute for Nuclear Research in Dubna, Russia (Figs. 4.114.1 and 4.114.2) and the Lawrence Livermore Laboratory in the USA synthesized flerovium. They used nuclear reaction experiments to eventually produce 287Fl by cross-bombardments of 48Ca with both (even-A) 242Pu and (odd-A) 245Cm. The intermediate nuclide 283Cn was observed with known decay characteristics that established the synthesis of flerovium [668], [669]. Flerovium has no known isotopic applications aside from scientific research.
Flerovium was first produced by scientists working at the Joint Institute for Nuclear Research in Dubna, Russia in 1998. They bombarded atoms of plutonium with ions of calcium. This produced a single atom of flerovium-289, an isotope with a half-life of about 21 seconds. Flerovium's most stable isotope, flerovium-289, has a half-life of about 0.97 seconds. It decays into copernicium-285 through alpha decay.
Flerovium is radioactive and has the symbol Fl and the atomic number 114. The element is named after Russian physicist Georgy Flyorov, who founded the Joint Institute for Nuclear Research in Dubna, Russia, where the element was first discovered in 1999.
Element 114 has a 30-second half-life, which is much longer than element 112's. This is evidence of the "island of stability" that was predicted to occur around element 114 (where the combination of protons and neutrons would combine to make a stable structure).
A beam containing 48Ca was aimed into a244Pu target to make this atom.
The name Flerovium was adopted by IUPAC on May 31, 2012.
No macroscopic sample of flerovium has ever been prepared, so its appearance is not known. Calculations generally predict a dense metal, possibly with comparatively low cohesive energy, but color, texture, and ordinary bulk properties remain unobserved.
Flerovium has no practical use outside basic scientific research. Individual atoms are produced to study nuclear stability, decay chains, and the chemistry of superheavy elements near the predicted island of stability. Its isotopes are too short-lived and too difficult to make for use in materials, medicine, industry, or routine analytical standards. Reported applications are experimental targets, detectors, and chemical-separation studies rather than uses of stored flerovium material.
Since only a few atoms of flerovium have ever been produced, it currently has no uses outside of basic scientific research.
Flerovium chemistry has been probed only with single atoms, mainly by observing adsorption behavior after production and decay. It is placed in group 14, but relativistic stabilization of the 7p₁/₂ electrons is expected to make the +2 state more accessible and the +4 state less robust than in lighter congeners such as lead. Specific compounds have not been isolated in weighable amounts. Theoretical studies consider species such as flerovium dioxide, FlO₂, and flerovium tetrachloride, FlCl₄, but their stability and structures are predictions rather than established preparative chemistry.
See more information at the Flerovium compound page.
The direct radiological hazard of flerovium is isotope-specific, but any produced atom decays rapidly by alpha emission or spontaneous fission through radioactive daughter nuclides. Macroscopic handling hazards are not characterized because no bulk material exists. In practice, safety concerns belong to accelerator operations, intense ion beams, radioactive targets, recoil products, and contaminated experimental hardware rather than to stored flerovium compounds.
Flerovium has no confirmed natural occurrence and no known environmental cycle. Atoms made in laboratories decay long before they could disperse as a persistent environmental contaminant. Any environmental relevance is tied to small amounts of target materials and activation products from nuclear research facilities, not to flerovium itself as a mobile or bioavailable element.
Flerovium has no commodity market, industrial supply chain, or recoverable stock. It is produced only in specialized accelerator experiments, commonly by bombarding actinide targets with heavy ions and identifying a few atoms through their decay sequences. The limiting costs are accelerator time, target preparation, radiochemical and detector infrastructure, and the rarity of successful fusion-evaporation events. There is no recycling economy for flerovium, because produced atoms decay before collection as material.
Made by bombarding plutonium-244 with calcium-48.
Flerovium is not known as a naturally occurring cosmic or planetary element. Superheavy nuclei may be formed transiently in extreme neutron-rich events, but isotopes of flerovium with known or expected half-lives would not survive over geological or cosmic timescales. Its significance is mainly as a laboratory probe of nuclear shell effects in very heavy atoms.
- Flerovium was named for the Flerov Laboratory of Nuclear Reactions in Dubna.
- Only single atoms have been used in chemical experiments on flerovium.
- Its group placement does not guarantee lead-like chemistry because relativistic effects are large.
- Gas-phase studies suggest unusually weak interaction with gold surfaces, but the data set is very small.
- Decay-chain identification is central to confirming flerovium production.
画像
性質
物理的性質
- 原子半径（経験値）
- 180 pm 全元素の原子半径（経験値）を比較 →
- 密度
- 9928 kg/m³ 全元素の密度を比較 →
- 標準温度・圧力（STP）での相
- 気体 全元素の標準温度・圧力（STP）での相を比較 →
- 沸点
- -63.15 °C 全元素の沸点を比較 →
化学的性質
- 電子親和力
- -0.5 eV (負の値—この原子は電子を取り込まないと予測される)
- 酸化数
- 0, +1, +2, +4, +6 全元素の酸化数を比較 →
- 価電子
- 27 全元素の価電子を比較 →
- 電子配置
- [Rn] 7s2 7p2 5f14 6d10 (予測値)
熱力学的性質
データなし
原子核
- 陽子数
- 114 全元素の陽子数を比較 →
- 中性子数
- 176 全元素の中性子数を比較 →
- 既知の同位体
- 8 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 →
- 質量数（最も安定な同位体）
- 289
- 最も安定な同位体
- Fl-290
- 発見年
- 1998
存在度
データなし
結晶構造
データなし
電子構造
- 各電子殻の電子数
- 14, 10, 27 全元素の各電子殻の電子数を比較 →
識別子
- CAS登録番号
- 54085-16-4 全元素のCAS登録番号を比較 →
- InChI
- InChI=1S/Fl
- InChI Key
- WIHJCBVMYKIGOT-UHFFFAOYSA-N
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 |
|---|---|---|---|
| 288 放射性 | 288.18757 ± 0.00091 | データなし | 653 ms |
| 287 放射性 | 287.18678 ± 0.00066 | データなし | 510 ms |
| 285 放射性 | 285.18364 ± 0.00047 | データなし | 210 ms |
| 286 放射性 | 286.18423 ± 0.00071 | データなし | 130 ms |
| 290 放射性 | 290.191875 ± 0.000752 | データなし | 80 秒 |
相／状態
理由: 沸点（-63.15 °C）より88.1 °C高い
模式図、実際の縮尺とは異なります
相転移点
密度
標準条件下
現在の温度Tにおいて理想気体の状態方程式で推定
固相の結晶構造データはありません
同位体 (5)
| 質量数 | 原子質量（u） | 天然存在比 | 半減期 | 崩壊形式 | |
|---|---|---|---|---|---|
| 288 放射性 | 288.18757 ± 0.00091 | データなし | 653 ms | α ≈100%SF ? | |
| 287 放射性 | 287.18678 ± 0.00066 | データなし | 510 ms | α ≈100%SF ? | |
| 285 放射性 | 285.18364 ± 0.00047 | データなし | 210 ms | α ≈100%SF<20% | |
| 286 放射性 | 286.18423 ± 0.00071 | データなし | 130 ms | α =59±1.1%SF =41±1.1% | |
| 290 放射性 | 290.191875 ± 0.000752 | データなし | 80 秒 | α ≈100%SF ?β+<50% |
詳細な性質
共有結合半径（詳細）
- 共有結合半径（Pyykkö）
- 143 pm
番号付けの尺度
- Mendeleev
- 92
分極率と分散
- 双極子分極率
- 31 a.u.
- 双極子分極率（不確かさ）
- 4 a.u.
専門参考データ
同位体の崩壊形式 (17)
| 同位体 | モード | 強度 |
|---|---|---|
| 284 | SF | 100% |
| 284 | A | — |
| 285 | A | 100% |
| 285 | SF | 20% |
| 286 | A | 59% |
| 286 | SF | 41% |
| 287 | A | 100% |
| 287 | SF | — |
| 288 | A | 100% |
| 288 | SF | — |
追加データ
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
Not Applicable
参考文献 (1)
- [5] Flerovium https://education.jlab.org/itselemental/ele114.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
参考文献 (1)
- [5] Flerovium https://education.jlab.org/itselemental/ele114.html
参考文献
(8)
Data deposited in or computed by PubChem
The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.
Element data are cited from the Atomic weights of the elements (an IUPAC Technical Report). The IUPAC periodic table of elements can be found at https://iupac.org/what-we-do/periodic-table-of-elements/. Additional information can be found within IUPAC publication doi:10.1515/pac-2015-0703 Copyright © 2020 International Union of Pure and Applied Chemistry.
The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.
Thomas Jefferson National Accelerator Facility (Jefferson Lab) is one of 17 national laboratories funded by the U.S. Department of Energy. The lab's primary mission is to conduct basic research of the atom's nucleus using the lab's unique particle accelerator, known as the Continuous Electron Beam Accelerator Facility (CEBAF). For more information visit https://www.jlab.org/
The periodic table at the LANL (Los Alamos National Laboratory) contains basic element information together with the history, source, properties, use, handling and more. The provenance data may be found from the link under the source name.
The periodic table contains NIST's critically-evaluated data on atomic properties of the elements.
This section provides all form of data related to element Flerovium.