Meitnerium (Mt)
transition-metalSolid
मानक परमाणु भार
[278]इलेक्ट्रॉन विन्यास
[Rn] 7s2 5f14 6d7 (परिकलित)गलनांक
उपलब्ध नहींक्वथनांक
उपलब्ध नहींघनत्व
3.74e+4 kg/m³ऑक्सीकरण अवस्थाएँ
+1, +3, +4, +6, +8, +9विद्युतऋणात्मकता (पॉलिंग)
उपलब्ध नहींआयनन ऊर्जा (प्रथम)
उपलब्ध नहींखोज का वर्ष
1982परमाणु त्रिज्या
128 pmविवरण
Meitnerium is a synthetic transactinide element in group 9, below cobalt, rhodium, and iridium. It has been made only atom by atom in heavy-ion accelerator experiments, and all known isotopes are radioactive with very short half-lives. Its chemistry is expected to be influenced strongly by relativistic effects, but direct chemical data are extremely limited or absent. The element is chiefly significant for nuclear-structure studies of the heaviest nuclei.
Meitnerium does not occur naturally in the Earth’s crust. Meitnerium was first synthesized by German scientists at the GSI Center for Heavy Ion Research in Darmstadt, Germany in 1984 using the nuclear reaction 209Bi (58Fe, n) 266MtHs. The element is named for the physicist, Lise Meitner (Fig. IUPAC.109.1), who discovered the element protactinium [653], [655]. Meitnerium is used only for scientific research.
Meitnerium is named after Lise Meitner.
Meitnerium was first produced by Peter Armbruster, Gottfried Münzenber and their team working at the Gesellschaft für Schwerionenforschung in Darmstadt, Germany in 1982. They bombarded atoms of bismuth-209 with ions of iron-58 with a device known as a linear accelerator. This produced atoms of meitnerium-266, an isotope with a half-life of about 3.8 milliseconds (0.0038 seconds), and a free neutron. Meitnerium's most stable isotope, meitnerium-278, has a half-life of about 8 seconds. It decays into bohrium-274 through alpha decay.
On August 29, 1982, physicists at the Heavy Ion Research Laboratory, Darmstadt, West Germany made and identified element 109 by bombing a target of 209Bi with accelerated nuclei of 58Fe. If the combined energy of two nuclei is sufficiently high, the repulsive forces between the nuclei can be overcome.
In this experiment, a week of target bombardment was required to produce a single fused nucleus. The team confirmed the existence of element 109 by four independent measurements. The newly formed atom recoiled from the target at predicted velocity and was separated from smaller, faster nuclei by a newly developed velocity filter. The time of flight to the detector and the striking energy were measured and found to match predicted values.
The nucleus of 266X started to decay 5 ms after striking the detector. A high-energy alpha particle was emitted, producing 262/107X. This in turn emitted an alpha particle, becoming 258/105Db, which in turn captured an electron and became 258/104Rf. This in turn decayed into other nuclides. This experiment demonstrated the feasibility of using fusion techniques as a method of making new, heavy nuclei.
No macroscopic sample of meitnerium has been prepared, so its visible appearance and bulk physical properties are unknown. Calculations usually treat it as a dense metallic solid under ordinary conditions, broadly analogous to the heavier platinum-group metals, but this remains unobserved.
Meitnerium has no practical commercial, medical, or industrial use. Its use is confined to basic research, where individual atoms are produced and identified through their decay chains. These experiments test models of nuclear stability, fusion-evaporation reactions, and detector methods for superheavy elements. Some meitnerium isotopes also appear as daughters in decay chains from still heavier synthetic elements, providing evidence used to link and verify those chains.
Since only small amounts of meitnerium have ever been produced, it currently has no uses outside of basic scientific research.
No bulk compound of meitnerium has been isolated, and its chemical behavior has not been characterized in ordinary laboratory quantities. As a group 9 element it is expected to show some resemblance to iridium, with metallic bonding and possible positive oxidation states, especially +3, in suitable compounds. Theoretical work has considered species such as meitnerium hexafluoride, MtF₆, and oxo or halide complexes, but these predictions have not been confirmed by direct compound isolation. Relativistic effects may alter ligand bonding compared with lighter homologues.
See more information at the Meitnerium compound page.
The safety concerns for meitnerium are radiological rather than chemical, because only individual atoms are produced. Known isotopes decay mainly by alpha emission and sometimes through decay modes that lead quickly to other radioactive nuclides. Chemical toxicity has not been measured and is not practically separable from the radiation hazard. Experiments require accelerator shielding, contamination control for radioactive targets and recoils, and remote handling appropriate to the associated nuclear materials.
Meitnerium has no confirmed natural occurrence and no known environmental cycle. Atoms made in accelerators are formed in targets, recoil separators, or detector systems and decay rapidly. The quantities are far too small and short-lived for observed transport, bioaccumulation, or ecological effects. Any environmental concern from its production would instead come from activated equipment, target materials, and daughter radionuclides handled in the laboratory.
Meitnerium has no commodity market, no industrial supply chain, and no recoverable stock. It is produced only in specialized nuclear physics facilities by bombarding heavy target nuclei with accelerated ions, commonly in fusion-evaporation reactions designed to make a few atoms. The limiting factors are accelerator time, target preparation, detection efficiency, and the very low reaction probability, not raw material demand. Recycling is not meaningful for the element itself because the atoms decay before collection as material.
Obtained by bombarding bismuth-209 with iron-58.
Meitnerium is not expected to be a primordial element, because its known isotopes are far too short-lived to survive since the formation of the Solar System. It may be formed fleetingly in extreme nucleosynthetic environments, if at all, but no extraterrestrial occurrence has been observed. Its relevance to cosmic chemistry is mainly theoretical, in discussions of the limits of nuclear stability.
- Meitnerium was first identified in experiments at GSI Darmstadt in 1982.
- It is named for the physicist Lise Meitner.
- The first reported isotope was ²⁶⁶Mt, made from bismuth and iron nuclei.
- Only atom-at-a-time nuclear decay data are available for most meitnerium isotopes.
- Meitnerium sits in the same periodic group as iridium, but its chemistry remains essentially untested.
चित्र
गुण
भौतिक
- परमाणु त्रिज्या (आनुभविक)
- 128 pm सभी तत्वों की परमाणु त्रिज्या (आनुभविक) की तुलना करें →
- घनत्व
- 3.74 × 104 kg/m³ सभी तत्वों की घनत्व की तुलना करें →
रासायनिक
- इलेक्ट्रॉन बंधुता
- 1.7 eV
- आयनन ऊर्जा (पंचम)
- 50.000172 eV सभी तत्वों की आयनन ऊर्जा (पंचम) की तुलना करें →
- ऑक्सीकरण अवस्थाएँ
- +1, +3, +4, +6, +8, +9 सभी तत्वों की ऑक्सीकरण अवस्थाएँ की तुलना करें →
- संयोजकता इलेक्ट्रॉन
- 25 सभी तत्वों की संयोजकता इलेक्ट्रॉन की तुलना करें →
- इलेक्ट्रॉन विन्यास
- [Rn] 7s2 5f14 6d7 (परिकलित)
ऊष्मागतिक
उपलब्ध नहीं
नाभिकीय
- प्रोटॉन
- 109 सभी तत्वों की प्रोटॉन की तुलना करें →
- न्यूट्रॉन
- 170 सभी तत्वों की न्यूट्रॉन की तुलना करें →
- ज्ञात समस्थानिक
- 18 सभी तत्वों की ज्ञात समस्थानिक की तुलना करें →
- स्थिर समस्थानिक
- 0 सभी तत्वों की स्थिर समस्थानिक की तुलना करें →
- द्रव्यमान संख्या (सबसे स्थिर)
- 278
- सबसे स्थिर समस्थानिक
- Mt-279
- खोज का वर्ष
- 1982
प्रचुरता
उपलब्ध नहीं
क्रिस्टल संरचना
उपलब्ध नहीं
इलेक्ट्रॉनिक संरचना
- प्रति कोश इलेक्ट्रॉन
- 7, 25 सभी तत्वों की प्रति कोश इलेक्ट्रॉन की तुलना करें →
पहचानकर्ता
- CAS संख्या
- 54038-01-6 सभी तत्वों की CAS संख्या की तुलना करें →
- InChI
- InChI=1S/Mt
- InChI कुंजी
- VAJSJTKWMRUWBF-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 |
|---|---|---|---|
| 274 रेडियोधर्मी | 274.14724 ± 0.00038 | उपलब्ध नहीं | 850 ms |
| 270 रेडियोधर्मी | 270.14033 ± 0.00018 | उपलब्ध नहीं | 800 ms |
| 273 रेडियोधर्मी | 273.1444 ± 0.00052 | उपलब्ध नहीं | 800 ms |
| 276 रेडियोधर्मी | 276.15159 ± 0.00059 | उपलब्ध नहीं | 700 ms |
| 271 रेडियोधर्मी | 271.14074 ± 0.00035 | उपलब्ध नहीं | 400 ms |
प्रावस्था / अवस्था
प्रावस्था/अवस्था का डेटा उपलब्ध नहीं है
परमाणु स्पेक्ट्रम
94 में से 10 दिखाए जा रहे हैं। आयन के आवेश के अनुसार आरोही क्रम में व्यवस्थित।
उपलब्ध ऊर्जा स्तर डेटा ?
| आयन | आवेश | स्तर |
|---|---|---|
| Mt V | +4 | 2 |
| Mt VI | +5 | 1 |
| Mt VII | +6 | 1 |
| Mt VIII | +7 | 2 |
| Mt IX | +8 | 2 |
| Mt X | +9 | 2 |
| Mt XI | +10 | 2 |
| Mt XII | +11 | 2 |
| Mt XIII | +12 | 2 |
| Mt XIV | +13 | 2 |
प्रावस्था/अवस्था का डेटा उपलब्ध नहीं है
यौगिक
समस्थानिक (5)
| द्रव्यमान संख्या | परमाणु द्रव्यमान (u) | प्राकृतिक प्रचुरता | अर्धायु | क्षय का प्रकार | |
|---|---|---|---|---|---|
| 274 रेडियोधर्मी | 274.14724 ± 0.00038 | उपलब्ध नहीं | 850 ms | α =100% | |
| 270 रेडियोधर्मी | 270.14033 ± 0.00018 | उपलब्ध नहीं | 800 ms | α ≈100% | |
| 273 रेडियोधर्मी | 273.1444 ± 0.00052 | उपलब्ध नहीं | 800 ms | α ?SF ? | |
| 276 रेडियोधर्मी | 276.15159 ± 0.00059 | उपलब्ध नहीं | 700 ms | α =100% | |
| 271 रेडियोधर्मी | 271.14074 ± 0.00035 | उपलब्ध नहीं | 400 ms | α ? |
विस्तृत गुण
सहसंयोजक त्रिज्याएँ (विस्तृत)
- सहसंयोजक त्रिज्या (प्यूक्को)
- 129 pm
- सहसंयोजक त्रिज्या (प्यूक्को, द्विबंध)
- 125 pm
- सहसंयोजक त्रिज्या (प्यूक्को, त्रिबंध)
- 113 pm
संख्यांकन मापक्रम
- Mendeleev
- 66
ध्रुवणीयता और परिक्षेपण
- द्विध्रुव ध्रुवणीयता
- 34 a.u.
- द्विध्रुव ध्रुवणीयता (अनिश्चितता)
- 3 a.u.
ऑक्सीकरण अवस्था की श्रेणियाँ
उन्नत संदर्भ डेटा
समस्थानिक क्षय के प्रकार (26)
| समस्थानिक | मोड | तीव्रता |
|---|---|---|
| 265 | A | — |
| 266 | A | 100% |
| 266 | SF | — |
| 267 | A | — |
| 268 | A | 100% |
| 269 | A | — |
| 270 | A | 100% |
| 271 | A | — |
| 272 | A | — |
| 272 | SF | — |
अतिरिक्त डेटा
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
Not Applicable
संदर्भ (1)
- [5] Meitnerium https://education.jlab.org/itselemental/ele109.html
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
Not Applicable
संदर्भ (1)
- [5] Meitnerium https://education.jlab.org/itselemental/ele109.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 Meitnerium.