Roentgenium (Rg)
transition-metalExpected to be a Solid
मानक परमाणु भार
281 uइलेक्ट्रॉन विन्यास
[Rn] 7s2 5f14 6d9 (पूर्वानुमानित)गलनांक
उपलब्ध नहींक्वथनांक
उपलब्ध नहींघनत्व
2.87e+4 kg/m³ऑक्सीकरण अवस्थाएँ
−1, +1, +3, +5विद्युतऋणात्मकता (पॉलिंग)
उपलब्ध नहींआयनन ऊर्जा (प्रथम)
उपलब्ध नहींखोज का वर्ष
1994परमाणु त्रिज्या
138 pmविवरण
Roentgenium is a synthetic transactinide element in group 11, below gold. It has been made only one atom at a time in heavy-ion fusion experiments, and all confirmed isotopes are highly radioactive and short-lived. Its chemistry has not been established experimentally in bulk or solution. Relativistic calculations generally place it among the coinage metals, but with properties that may differ appreciably from lighter homologues.
Roentgenium does not occur naturally in the Earth’s crust. Roentgenium was first synthesized by an international team of scientists from the GSI in Darmstadt, Germany, the Joint Institute for Nuclear Research (JINR) in Dubna, Russia, the Comenius University in Bratislava, Slovakia, and the University of Jyväskylä, Finland at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany in 1994, using the nuclear reaction 209Bi (64Ni, n) 272Rg. The credit for the first synthesis was confirmed in 2003. The element was named after Wilhelm Conrad Roentgen (Fig. IUPAC.111.1), who discovered X-rays in 1895 [660], [661], [662]. Roentgenium has no known isotopic applications aside from scientific research.
Roentgenium is named after Wilhelm Conrad Röntgen.
Roentgenium was first produced by Peter Armbruster, Gottfried Münzenber and their team working at the Gesellschaft für Schwerionenforschung in Darmstadt, Germany in late 1994. They bombarded atoms of bismuth-209 with ions of nickel-64 with a device known as a linear accelerator. This produced three atoms of roentgenium-272, an isotope with a half-life of about 1.5 milliseconds (0.0015 seconds), and a free neutron. Roentgenium's most stable isotope, roentgenium-281, has a half-life of about 26 seconds and decays through spontaneous fission.
Discovered by Gesellschaft Schwerionenforschung (GSI) in Darmstadt, in 1994. Reasearch group of S. Hofmann, V. Ninov, F.P. Hessberger, P. Armbruster, H. Folger, G. Munzenberg, H.J. Schott, and others.
No macroscopic sample of roentgenium has ever been prepared, so its appearance is unknown. A bulk metal, if it could exist long enough, is expected from theory to be dense and metallic, but color, surface behavior, and ordinary physical constants have not been measured.
Roentgenium has no practical, commercial, medical, or industrial use. Its only use is in nuclear research, where individual atoms and their decay chains help test models of heavy-element formation, nuclear stability, and alpha decay. Experiments involving roentgenium also support the identification of neighboring superheavy nuclei, but the element is not available as a material for devices, tracers, or chemical applications.
Since only a few atoms of roentgenium have ever been produced, it currently has no uses outside of basic scientific research.
No confirmed roentgenium compound has been isolated or characterized. The element is expected to show group 11 chemistry in some respects, but strong relativistic effects make detailed predictions uncertain. The +1 and +3 oxidation states are commonly discussed in theoretical work, with possible analogies to gold compounds such as gold(III) chloride, AuCl₃, rather than to the more stable simple chemistry of copper or silver. Proposed species such as roentgenium fluorides or chlorides remain predictions, not observed substances.
See more information at the Roentgenium compound page.
The safety properties of roentgenium are governed by radioactivity rather than ordinary chemical toxicity. Known isotopes decay rapidly, mainly through alpha decay and spontaneous fission pathways within decay chains. The quantities produced are far below a macroscopic hazard under normal laboratory containment, but any experiment requires specialized radiological controls for heavy-ion target materials, recoil products, and short-lived radioactive daughters.
Roentgenium has no confirmed natural occurrence and no environmental cycle. Any atoms produced in a laboratory decay before they could disperse or participate in ordinary geochemical processes. Environmental relevance is therefore limited to controlled accelerator facilities and to the management of irradiated targets, catcher foils, and associated radioactive residues from superheavy-element experiments.
Roentgenium is not a commodity and has no market price, supply chain, or recycling practice. Production requires a heavy-ion accelerator, rare target materials, and long experiments with extremely low atom yields. The element is identified through decay correlations rather than collected as a product. Economic considerations are those of publicly or institutionally funded nuclear-physics research, including accelerator time, target preparation, detector systems, and radiological handling.
Made by bombarding bismuth-209 with nickel-60.
Roentgenium is not expected to be a persistent cosmic element because its known isotopes are too unstable. If nuclei with 111 protons are formed transiently in extreme nucleosynthetic environments, they would decay quickly unless an unknown much longer-lived isotope exists. No roentgenium has been detected in stars, meteorites, planets, or terrestrial minerals.
- Roentgenium was named in honor of Wilhelm Conrad Röntgen, discoverer of X-rays.
- Its identification relies on linking a few decay events to known daughter nuclei.
- The longest-lived confirmed isotopes still have half-lives far too short for chemical stockpiles.
- Roentgenium lies in the same periodic-table group as copper, silver, and gold.
- Chemical experiments have not yet established a measured oxidation state for roentgenium.
चित्र
गुण
भौतिक
- परमाणु त्रिज्या (आनुभविक)
- 138 pm सभी तत्वों की परमाणु त्रिज्या (आनुभविक) की तुलना करें →
- घनत्व
- 2.87 × 104 kg/m³ सभी तत्वों की घनत्व की तुलना करें →
रासायनिक
- इलेक्ट्रॉन बंधुता
- 1.6 eV
- ऑक्सीकरण अवस्थाएँ
- −1, +1, +3, +5 सभी तत्वों की ऑक्सीकरण अवस्थाएँ की तुलना करें →
- संयोजकता इलेक्ट्रॉन
- 2 सभी तत्वों की संयोजकता इलेक्ट्रॉन की तुलना करें →
- इलेक्ट्रॉन विन्यास
- [Rn] 7s2 5f14 6d9 (पूर्वानुमानित)
ऊष्मागतिक
उपलब्ध नहीं
नाभिकीय
- प्रोटॉन
- 111 सभी तत्वों की प्रोटॉन की तुलना करें →
- न्यूट्रॉन
- 171 सभी तत्वों की न्यूट्रॉन की तुलना करें →
- ज्ञात समस्थानिक
- 15 सभी तत्वों की ज्ञात समस्थानिक की तुलना करें →
- स्थिर समस्थानिक
- 0 सभी तत्वों की स्थिर समस्थानिक की तुलना करें →
- द्रव्यमान संख्या (सबसे स्थिर)
- 282
- सबसे स्थिर समस्थानिक
- Rg-282
- खोज का वर्ष
- 1994
प्रचुरता
उपलब्ध नहीं
क्रिस्टल संरचना
उपलब्ध नहीं
इलेक्ट्रॉनिक संरचना
- प्रति कोश इलेक्ट्रॉन
- 14, 9, 2 सभी तत्वों की प्रति कोश इलेक्ट्रॉन की तुलना करें →
पहचानकर्ता
- CAS संख्या
- 54386-24-2 सभी तत्वों की CAS संख्या की तुलना करें →
- InChI
- InChI=1S/Rg
- InChI कुंजी
- LJROPTGWFUZRDB-UHFFFAOYSA-N
इलेक्ट्रॉन विन्यास पूर्वानुमानित
——इस आयन के लिए इलेक्ट्रॉन विन्यास का डेटा उपलब्ध नहीं है।
परमाणु मॉडल
समस्थानिक न्यूट्रॉन की संख्या, द्रव्यमान और स्थिरता बदलते हैं — उदासीन परमाणु का इलेक्ट्रॉन विन्यास नहीं।
उपलब्ध नहीं
सांकेतिक परमाणु मॉडल, वास्तविक अनुपात में नहीं।
परमाणु पहचान-चिह्न
उत्सर्जन / अवशोषण स्पेक्ट्रम
समस्थानिक वितरण
कोई स्थिर समस्थानिक नहीं है।
| द्रव्यमान संख्या | परमाणु द्रव्यमान (u) | प्राकृतिक प्रचुरता | अर्धायु |
|---|---|---|---|
| 279 रेडियोधर्मी | 279.16272 ± 0.00051 | उपलब्ध नहीं | 170 ms |
| 282 रेडियोधर्मी | 282.16912 ± 0.00072 | उपलब्ध नहीं | 130 सेकंड |
| 285 रेडियोधर्मी | 285.175771 ± 0.000644 | उपलब्ध नहीं | 30 सेकंड |
| 274 रेडियोधर्मी | 274.15525 ± 0.00019 | उपलब्ध नहीं | 20 ms |
| 281 रेडियोधर्मी | 281.16636 ± 0.00089 | उपलब्ध नहीं | 19 सेकंड |
प्रावस्था / अवस्था
प्रावस्था/अवस्था का डेटा उपलब्ध नहीं है
प्रावस्था/अवस्था का डेटा उपलब्ध नहीं है
यौगिक
समस्थानिक (5)
| द्रव्यमान संख्या | परमाणु द्रव्यमान (u) | प्राकृतिक प्रचुरता | अर्धायु | क्षय का प्रकार | |
|---|---|---|---|---|---|
| 279 रेडियोधर्मी | 279.16272 ± 0.00051 | उपलब्ध नहीं | 170 ms | α =100% | |
| 282 रेडियोधर्मी | 282.16912 ± 0.00072 | उपलब्ध नहीं | 130 सेकंड | α =100% | |
| 285 रेडियोधर्मी | 285.175771 ± 0.000644 | उपलब्ध नहीं | 30 सेकंड | α ?SF ? | |
| 274 रेडियोधर्मी | 274.15525 ± 0.00019 | उपलब्ध नहीं | 20 ms | α ≈100% | |
| 281 रेडियोधर्मी | 281.16636 ± 0.00089 | उपलब्ध नहीं | 19 सेकंड | SF =87±0.8%α =13±0.8% |
विस्तृत गुण
सहसंयोजक त्रिज्याएँ (विस्तृत)
- सहसंयोजक त्रिज्या (प्यूक्को)
- 121 pm
- सहसंयोजक त्रिज्या (प्यूक्को, द्विबंध)
- 116 pm
- सहसंयोजक त्रिज्या (प्यूक्को, त्रिबंध)
- 118 pm
संख्यांकन मापक्रम
- Mendeleev
- 74
ध्रुवणीयता और परिक्षेपण
- द्विध्रुव ध्रुवणीयता
- 32 a.u.
- द्विध्रुव ध्रुवणीयता (अनिश्चितता)
- 6 a.u.
ऑक्सीकरण अवस्था की श्रेणियाँ
उन्नत संदर्भ डेटा
समस्थानिक क्षय के प्रकार (22)
| समस्थानिक | मोड | तीव्रता |
|---|---|---|
| 272 | A | 100% |
| 273 | A | — |
| 274 | A | 100% |
| 275 | A | — |
| 276 | A | — |
| 276 | SF | — |
| 277 | A | — |
| 277 | SF | — |
| 278 | A | 100% |
| 279 | A | 100% |
अतिरिक्त डेटा
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
Not Applicable
संदर्भ (1)
- [5] Roentgenium https://education.jlab.org/itselemental/ele111.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
संदर्भ (1)
- [5] Roentgenium https://education.jlab.org/itselemental/ele111.html
संदर्भ
(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 Roentgenium.