Copernicium (Cn)
transition-metalExpected to be a Solid
標準原子量
[285]電子配置
[Rn] 7s2 5f14 6d10 (予測値)融点
データなし沸点
-165.15 °C密度
1.4e+4 kg/m³酸化数
+2, +4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
1996原子半径
147 pm詳細
Copernicium is a synthetic transactinide element in group 12, below zinc, cadmium, and mercury. It is known only from accelerator experiments that create individual atoms of short-lived isotopes. Relativistic effects are expected to make its chemistry unusually noble for a group 12 element, with weak metallic bonding and a comparatively volatile elemental state. Its confirmed properties are therefore mainly nuclear, while its chemical behavior remains partly experimental and partly theoretical.
Copernicium does not occur naturally in the Earth’s crust. Copernicium was synthesized by scientists at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany in 1996 (Fig. IUPAC.112.1). Sigurd Hofmann and an international team of scientists used the nuclear reaction 208Pb (70Zn, n) 277Cn. The observed alpha decays led to the known nuclide, 269Sg. The name, copernicium, was given to element 112 to honor astronomer Nicholas Copernicus, who is known for his heliocentric theory of how the planets orbit the Sun [663], [664]. Copernicium has no known isotopic applications aside from scientific research.
Copernicium is named after the astronomer Nicolaus Copernicus.
Copernicium was first produced by Peter Armbruster, Gottfried Münzenber and their team working at the Gesellschaft für Schwerionenforschung in Darmstadt, Germany on February 9, 1996. They bombarded atoms of lead with ions of zinc with a device known as a linear accelerator. This produced atoms of copernicium-277, an isotope with a half-life of about 0.24 milliseconds (0.00024 seconds). Copernicium's most stable isotope, copernicium-285, has a half-life of about 30 seconds. It decays into darmstadtium-281 through alpha decay.
On February 9, 1996, element 277Cn was created at the Gesellschaft fur Schwerionenforschung in Darmstadt, Germany by using the reaction 208Pb + 70Zn. Unlike element 110, Copernicium has properties more similar to radon than mercury, but due to its short half-life, it is difficult to study. As of 2011, Copernicum's most stable isotope has an atomic weight of 285.
No macroscopic sample of copernicium has been made, so its visible appearance is unknown. Calculations suggest a very volatile, weakly bound metal, possibly more gas-like in atom-at-a-time conditions than mercury, but this is not a directly observed bulk property.
Copernicium has no practical use outside scientific research. Its isotopes are produced one atom at a time to study superheavy nuclei, decay chains, and the influence of strong relativistic effects on chemical behavior. Experimental work with copernicium also helps test models used to predict the stability and chemistry of still heavier elements. No commercial, medical, structural, or electronic application is known or feasible with present production methods and isotope lifetimes.
Since only a few atoms of copernicium have ever been produced, it currently has no uses outside of basic scientific research.
Originally, the symbol Cp was recommended for Copernicium. That symbol was rejected because Cp had previously been used for the element lutetium which, prior to 1949, had cassiopeium as an alternative allowed name. Please see this file for additional details.
Copernicium chemistry has been investigated only in atom-at-a-time experiments and by theory. The element is expected to favor the +2 oxidation state in compounds, by analogy with group 12 elements, but strong relativistic stabilization of the 7s electrons may make neutral copernicium especially inert. Studies of adsorption behavior suggest that elemental Cn interacts weakly with gold surfaces compared with mercury. Predicted species include copernicium(II) fluoride, CnF₂, and copernicium(II) chloride, CnCl₂, but well-characterized bulk compounds do not exist.
See more information at the Copernicium compound page.
The hazards of copernicium are dominated by radioactivity rather than ordinary chemical toxicity. All known isotopes are short-lived and decay mainly by alpha emission, with some decay chains involving spontaneous fission. The element is produced in quantities far too small for conventional handling or environmental exposure. In laboratories, risk control concerns the accelerator target, recoil products, and radioactive decay products, not bulk copernicium material.
Copernicium has no confirmed natural occurrence and no environmental cycle. Any atoms formed naturally, if at all, would decay rapidly and would not accumulate. Laboratory production yields isolated atoms that decay within controlled experimental systems. Consequently, environmental behavior such as solubility, transport in soils or waters, bioaccumulation, and ecological effects has not been observed for copernicium.
Copernicium has no commodity market, industrial supply chain, or recoverable source. It is made in heavy-ion fusion experiments, commonly by bombarding heavy actinide targets with accelerated ions, followed by separation and detection of a few decay events. Production depends on specialized accelerators, rare target materials, long beam times, and highly sensitive detectors. The limiting factors are nuclear reaction cross sections and isotope half-lives, not ore availability or refining capacity. Recycling and substitution have no practical meaning for this element outside research planning.
Made by bombarding lead-208 with zinc-70.
Copernicium is not expected to be a primordial or cosmically abundant element because its known isotopes decay far too quickly to survive since nucleosynthesis. Superheavy nuclei may be formed fleetingly in extreme astrophysical neutron-rich events, but no stable or long-lived copernicium isotope is known. It has no established role in planetary chemistry or extraterrestrial materials.
- Copernicium was named for Nicolaus Copernicus.
- Its chemistry is strongly affected by relativistic stabilization of the 7s electrons.
- Only individual atoms have been studied experimentally.
- The most useful evidence for its chemistry comes from rapid gas-phase adsorption experiments.
- Copernicium sits below mercury but may be even more volatile.
- Its discovery was credited to work at GSI in Darmstadt, Germany.
画像
性質
物理的性質
- 原子半径（経験値）
- 147 pm 全元素の原子半径（経験値）を比較 →
- 密度
- 1.4 × 104 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
- -165.15 °C 全元素の沸点を比較 →
化学的性質
- 電子親和力
- -0.8 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
- +2, +4 全元素の酸化数を比較 →
- 価電子
- 2 全元素の価電子を比較 →
- 電子配置
- [Rn] 7s2 5f14 6d10 (予測値)
熱力学的性質
データなし
原子核
- 陽子数
- 112 全元素の陽子数を比較 →
- 中性子数
- 173 全元素の中性子数を比較 →
- 既知の同位体
- 13 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）
- 285
- 最も安定な同位体
- Cn-285
- 発見年
- 1996
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, 2 全元素の各電子殻の電子数を比較 →
識別子
- CAS登録番号
- 54084-26-3 全元素のCAS登録番号を比較 →
- InChI
- InChI=1S/Cn
- InChI Key
- NOTIIDSZELDPOP-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 |
|---|---|---|---|
| 277 放射性 | 277.16364 ± 0.00015 | データなし | 790 us |
| 281 放射性 | 281.16975 ± 0.00042 | データなし | 180 ms |
| 284 放射性 | 284.17416 ± 0.00091 | データなし | 102 ms |
| 276 放射性 | 276.16141 ± 0.00064 | データなし | 100 us |
| 279 放射性 | 279.16654 ± 0.0005 | データなし | 60 us |
相／状態
理由: 沸点（-165.15 °C）より190.1 °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 | |
|---|---|---|---|---|---|
| 277 放射性 | 277.16364 ± 0.00015 | データなし | 790 us | α =100% | |
| 281 放射性 | 281.16975 ± 0.00042 | データなし | 180 ms | α ≈100%SF ? | |
| 284 放射性 | 284.17416 ± 0.00091 | データなし | 102 ms | SF =100% | |
| 276 放射性 | 276.16141 ± 0.00064 | データなし | 100 us | α ?SF ? | |
| 279 放射性 | 279.16654 ± 0.0005 | データなし | 60 us | α ?SF ? |
詳細な性質
共有結合半径（詳細）
- 共有結合半径（Pyykkö）
- 122 pm
- 共有結合半径（Pyykkö、二重結合）
- 137 pm
- 共有結合半径（Pyykkö、三重結合）
- 130 pm
番号付けの尺度
- Mendeleev
- 80
分極率と分散
- 双極子分極率
- 28 a.u.
- 双極子分極率（不確かさ）
- 2 a.u.
酸化数の分類
専門参考データ
同位体の崩壊形式 (23)
| 同位体 | モード | 強度 |
|---|---|---|
| 276 | A | — |
| 276 | SF | — |
| 277 | A | 100% |
| 278 | A | — |
| 278 | SF | — |
| 279 | A | — |
| 279 | SF | — |
| 280 | A | — |
| 280 | SF | — |
| 281 | A | 100% |
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] Copernicium https://education.jlab.org/itselemental/ele112.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
参考文献 (1)
- [5] Copernicium https://education.jlab.org/itselemental/ele112.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 Copernicium.