Rutherfordium (Rf)
transition-metalSolid
標準原子量
263 u電子配置
[Rn] 7s2 5f14 6d2融点
2126.85 °C沸点
5526.85 °C密度
2.33e+4 kg/m³酸化数
+3, +4電気陰性度（Pauling）
データなし第1イオン化エネルギー
6.02 eV発見年
1964原子半径
150 pm詳細
Rutherfordium is a synthetic transactinide element and the first member of the 6d transition-metal series. All confirmed isotopes are radioactive and short-lived, so its chemistry is studied atom by atom. Chemical experiments show behavior broadly consistent with a group 4 element, analogous to hafnium and zirconium, with the +4 oxidation state dominant in aqueous and halide systems. Relativistic effects and nuclear instability make direct measurements difficult.
Rutherfordium does not occur naturally in the Earth’s crust. Credit for the first synthesis of this element is given jointly to Albert Ghiorso and his team at the University of California in Berkeley and Georgi Flerov and his team at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia. The element is named for Ernest Rutherford (Fig. IUPAC.104.1), who won the Nobel Prize for developing the theory of radioactive transformations [645].
Rutherfordium is of interest in particle physics research, but it has no commercial applications. 261Rf was one of the decay products used to confirm the synthesis of copernicium in a particle accelerator experiment [634].
Rutherfordium named after Ernest Rutherford.
Scientists working at the Joint Institute for Nuclear Research in Dubna, Russia, first reported the production of rutherfordium in 1964. They bombarded atoms of plutonium-242 with ions of neon-22, forming what they believed to be atoms of rutherfordium-260 and four free neutrons. In 1969, a group of scientists working at the Lawrence Radiation Laboratory, now known as the Lawrence Berkeley Laboratory, in Berkeley, California, attempted to confirm the Dubna group's discovery. Lacking the equipment needed to accelerate neon ions, the Berkeley group, led by Albert Ghiorso, bombarded atoms of californium-248 and californium-249 with ions of carbon-12 and carbon-13, producing atoms of rutherfordium-257, rutherfordium-258, rutherfordium-259 and rutherfordium-261. They were, however, unable to produce the same isotope as the Dubna group. Credit for the discovery of rutherfordium is still under debate. Rutherfordium's most stable isotope, rutherfordium-263, has a half-life of about 10 minutes and decays through spontaneous fission.
In 1964, workers at the Joint Nuclear Research Institute at Dubna (U.S.S.R.) bombarded plutonium with accelerated 113 to 115 MeV neon ions. By measuring fission tracks in a special glass with a microscope, they detected an isotope that decays by spontaneous fission. They suggested that this isotope, which had a half-life of 0.3 +/- 0.1 s might be 260-104, produced by the following reaction: 242Pu + 22Ne >260Rf +4n.
Element 104, the first transactinide element, is expected to have chemical properties similar to those of hafnium. It would, for example, form a relatively volatile compound with chlorine (a tetrachloride).
The Soviet scientists have performed experiments aimed at chemical identification, and have attempted to show that the 0.3-s activity is more volatile than that of the relatively nonvolatile actinide trichlorides. This experiment does not fulfill the test of chemically separating the new element from all others, but it provides important evidence for evaluation. Data issued by Soviet scientists reduced the half-life of the isotope they worked with from 0.3 to 0.15 s.
No macroscopic sample of rutherfordium has been prepared, and its visible appearance is unknown. Calculations generally treat it as a very heavy metallic solid under ordinary conditions, but this remains a prediction rather than an observed bulk property.
Rutherfordium has no practical use outside scientific research. It is produced in accelerator experiments to study the limits of the periodic table, transactinide nuclear stability, and the chemistry of single atoms. Individual isotopes have been used in decay-chain identification and in rapid chemical separations designed to compare group 4 behavior with zirconium and hafnium. There is no medical, industrial, structural, or consumer application for the element.
Due to the small amounts produced and its short half-life, there are currently no uses for rutherfordium outside of basic scientific research.
Rutherfordium chemistry has been inferred from very small numbers of atoms in fast gas-phase and aqueous experiments. The most important oxidation state is +4, matching its placement below hafnium. Volatile tetrachloride behavior has been studied for rutherfordium tetrachloride, RfCl₄, in comparison with zirconium tetrachloride, ZrCl₄, and hafnium tetrachloride, HfCl₄. In aqueous solution, hydrolysis, fluoride complexation, and chloride complexation indicate a hard, highly charged cation with group 4 character, although relativistic effects can alter detailed complex stability.
See more information at the Rutherfordium compound page.
The safety concern is radiological rather than chemical toxicity in ordinary handling, because only atom-scale quantities are produced. Hazards depend on the isotope and its decay products; many known isotopes decay by alpha emission, spontaneous fission, or both. Accelerator targets, collection systems, and contaminated apparatus require radiological controls, but rutherfordium itself is not encountered by the public or in commerce.
Rutherfordium has no confirmed natural environmental occurrence. Any atoms made in laboratories decay rapidly and are produced in quantities far too small to form an environmental reservoir or chemical cycle. Its environmental behavior as a bulk substance is therefore unobserved; only its predicted or atom-at-a-time chemical interactions can be compared with those of other group 4 metals.
Rutherfordium has no commodity market, no stockpiled supply, and no economic demand. Production requires heavy-ion accelerators, specialized targets, and rapid detection systems, yielding atoms or very small numbers of atoms for immediate study. Isotopes are made by nuclear reactions such as bombarding actinide targets with lighter ions, and the practical constraint is experimental access rather than raw-material value. Recycling and substitution are not relevant except in the general sense that other elements are used whenever a stable material is needed.
Made by bombarding californium-249 with beams of carbon-12 and 13, which produced an isotope with half lives of 4+ and 3 sec.
Rutherfordium is not expected to be a persistent cosmic element. Its known isotopes have half-lives far too short for primordial survival, and any atoms formed in extreme astrophysical nucleosynthesis would decay quickly into lighter nuclei. No extraterrestrial reservoir is known, and its significance in the universe is chiefly as a laboratory probe of very heavy nuclei.
- Rutherfordium was central to early naming disputes over the first transactinide elements.
- Its chemistry must often be completed before the atom decays.
- Gas-phase studies have compared RfCl₄ with the tetrachlorides of zirconium and hafnium.
- Some rutherfordium isotopes are identified through linked alpha-decay chains.
- The element is named for Ernest Rutherford.
画像
性質
物理的性質
- 原子半径（経験値）
- 150 pm 全元素の原子半径（経験値）を比較 →
- 密度
- 2.33 × 104 kg/m³ 全元素の密度を比較 →
- 標準温度・圧力（STP）での相
- 固体 全元素の標準温度・圧力（STP）での相を比較 →
- 融点
- 2126.85 °C 全元素の融点を比較 →
- 沸点
- 5526.85 °C 全元素の沸点を比較 →
化学的性質
- 電子親和力
- 0.65 eV
- 第1イオン化エネルギー
- 6.02 eV 全元素の第1イオン化エネルギーを比較 →
- 第2イオン化エネルギー
- 14.350049 eV 全元素の第2イオン化エネルギーを比較 →
- 第3イオン化エネルギー
- 23.840082 eV 全元素の第3イオン化エネルギーを比較 →
- 第4イオン化エネルギー
- 31.87011 eV 全元素の第4イオン化エネルギーを比較 →
- 第5イオン化エネルギー
- 64.00022 eV 全元素の第5イオン化エネルギーを比較 →
- 酸化数
- +3, +4 全元素の酸化数を比較 →
- 価電子
- 4 全元素の価電子を比較 →
- 電子配置
- [Rn] 7s2 5f14 6d2
熱力学的性質
データなし
原子核
- 陽子数
- 104 全元素の陽子数を比較 →
- 中性子数
- 162 全元素の中性子数を比較 →
- 既知の同位体
- 16 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）
- 267
- 最も安定な同位体
- Rf-266
- 発見年
- 1964
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
- 2, 8, 18, 32, 32, 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
- 53850-36-5 全元素のCAS登録番号を比較 →
- 項記号
- 3F2
- InChI
- InChI=1S/Rf
- InChI Key
- YGPLJIIQQIDVFJ-UHFFFAOYSA-N
電子配置 予測値
Rf: 5f¹⁴ 6d² 7s²[Rn] 5f¹⁴ 6d² 7s²1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p⁶ 5f¹⁴ 6d² 7s²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。
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 |
|---|---|---|---|
| 262 放射性 | 262.10992 ± 0.00024 | データなし | 250 ms |
| 254 放射性 | 254.10005 ± 0.0003 | データなし | 22.9 us |
| 260 放射性 | 260.10644 ± 0.00022 | データなし | 21 ms |
| 253 放射性 | 253.10044 ± 0.00044 | データなし | 13 ms |
| 258 放射性 | 258.103428 ± 0.000034 | データなし | 12.5 ms |
相／状態
理由: 融点（2126.85 °C）より2101.8 °C低い
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
標準条件下
原子スペクトル
全93件中10件を表示しています。 イオンの電荷の昇順で並べています。
準位データの収録状況 ?
| イオン | 電荷 | 準位 |
|---|---|---|
| Rf I | 0 | 2 |
| Rf II | +1 | 2 |
| Rf III | +2 | 2 |
| Rf IV | +3 | 2 |
| Rf V | +4 | 2 |
| Rf VI | +5 | 2 |
| Rf VII | +6 | 2 |
| Rf VIII | +7 | 2 |
| Rf IX | +8 | 2 |
| Rf X | +9 | 2 |
結晶構造のデータはありません
化合物
同位体 (5)
In 1969 Ghiorso, Nurmia, Harris, K.A.Y. Eskola, and P.L. Eskola of the University of California at Berkeley reported that they had positively identified two, and possibly three isotopes of Element 104. The group indicated that, after repeated attempts, they produced isotope 260104 reported by the Dubna groups in 1964.
| 質量数 | 原子質量（u） | 天然存在比 | 半減期 | 崩壊形式 | |
|---|---|---|---|---|---|
| 262 放射性 | 262.10992 ± 0.00024 | データなし | 250 ms | SF ≈100% | |
| 254 放射性 | 254.10005 ± 0.0003 | データなし | 22.9 us | SF ≈100%α<1.5% | |
| 260 放射性 | 260.10644 ± 0.00022 | データなし | 21 ms | SF ≈100%α ?β+ ? | |
| 253 放射性 | 253.10044 ± 0.00044 | データなし | 13 ms | SF ≈100%α ? | |
| 258 放射性 | 258.103428 ± 0.000034 | データなし | 12.5 ms | SF =95.1±1.6%α =4.9±1.6% |
詳細な性質
共有結合半径（詳細）
- 共有結合半径（Pyykkö）
- 157 pm
- 共有結合半径（Pyykkö、二重結合）
- 140 pm
- 共有結合半径（Pyykkö、三重結合）
- 131 pm
番号付けの尺度
- Mendeleev
- 46
分極率と分散
- 双極子分極率
- 112 a.u.
- 双極子分極率（不確かさ）
- 10 a.u.
酸化数の分類
専門参考データ
同位体の崩壊形式 (33)
| 同位体 | モード | 強度 |
|---|---|---|
| 253 | SF | 100% |
| 253 | A | — |
| 254 | SF | 100% |
| 254 | A | 1.5% |
| 255 | A | 52.8% |
| 255 | SF | 47.2% |
| 255 | B+ | 6% |
| 256 | SF | 99.7% |
| 256 | A | 0.3% |
| 257 | A | 89.3% |
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] Rutherfordium https://education.jlab.org/itselemental/ele104.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
参考文献 (1)
- [5] Rutherfordium https://education.jlab.org/itselemental/ele104.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. The provenance data that include data for atomic spectroscopy, X-ray and gamma ray, radiation dosimetry, nuclear physics, and condensed matter physics may be found from the link under the source name. Ref: https://www.nist.gov/pml/atomic-spectra-database
This section provides all form of data related to element Rutherfordium.