9 November 1994

The chemical element darmstadtium is discovered.

Darmstadtium, 110Ds
Darmstadtium
Pronunciation/dɑːrmˈstætiəm, -ˈʃtæt-/ (About this soundlisten)[1][2] (darm-S(H)TAT-ee-əm)
Mass number[281]
Darmstadtium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
Pt

Ds

(Uhq)
meitneriumdarmstadtiumroentgenium
Atomic number (Z)110
Groupgroup 10
Periodperiod 7
Blockd-block
Element category  Unknown chemical properties, but probably a transition metal
Electron configuration[Rn] 5f14 6d8 7s2 (predicted)[3]
Electrons per shell2, 8, 18, 32, 32, 16, 2 (predicted)[3]
Physical properties
Phase at STPsolid (predicted)[4]
Density (near r.t.)34.8 g/cm3 (predicted)[3]
Atomic properties
Oxidation states(0), (+2), (+4), (+6), (+8) (predicted)[3][5]
Ionization energies
  • 1st: 960 kJ/mol
  • 2nd: 1890 kJ/mol
  • 3rd: 3030 kJ/mol
  • (more) (all estimated)[3]
Atomic radiusempirical: 132 pm (predicted)[3][5]
Covalent radius128 pm (estimated)[6]
Other properties
Natural occurrencesynthetic
Crystal structurebody-centered cubic (bcc)
Body-centered cubic crystal structure for darmstadtium

(predicted)[4]
CAS Number54083-77-1
History
Namingafter Darmstadt, Germany, where it was discovered
DiscoveryGesellschaft für Schwerionenforschung (1994)
Main isotopes of darmstadtium
Iso­tope Abun­dance Half-life (t1/2) Decay mode Pro­duct
279Ds syn 0.2 s 10% α 275Hs
90% SF
281Ds syn 14 s 94% SF
6% α 277Hs
Category Category: Darmstadtium
| references

Darmstadtium is a chemical element with the symbol Ds and atomic number 110. It is an extremely radioactive synthetic element. The most stable known isotope, darmstadtium-281, has a half-life of approximately 12.7 seconds. Darmstadtium was first created in 1994 by the GSI Helmholtz Centre for Heavy Ion Research near the city of Darmstadt, Germany, after which it was named.

In the periodic table, it is a d-block transactinide element. It is a member of the 7th period and is placed in the group 10 elements, although no chemical experiments have yet been carried out to confirm that it behaves as the heavier homologue to platinum in group 10 as the eighth member of the 6d series of transition metals. Darmstadtium is calculated to have similar properties to its lighter homologues, nickel, palladium, and platinum.

Introduction

A graphic depiction of a nuclear fusion reaction
A graphic depiction of a nuclear fusion reaction. Two nuclei fuse into one, emitting a neutron. Reactions that created new elements to this moment were similar, with the only possible difference that several singular neutrons sometimes were released, or none at all.
External video
video icon Visualization of unsuccessful nuclear fusion, based on calculations by the Australian National University[7]

The heaviest[a] atomic nuclei are created in nuclear reactions that combine two other nuclei of unequal size[b] into one; roughly, the more unequal the two nuclei in terms of mass, the greater the possibility that the two react.[13] The material made of the heavier nuclei is made into a target, which is then bombarded by the beam of lighter nuclei. Two nuclei can only fuse into one if they approach each other closely enough; normally, nuclei (all positively charged) repel each other due to electrostatic repulsion. The strong interaction can overcome this repulsion but only within a very short distance from a nucleus; beam nuclei are thus greatly accelerated in order to make such repulsion insignificant compared to the velocity of the beam nucleus.[14] Coming close alone is not enough for two nuclei to fuse: when two nuclei approach each other, they usually remain together for approximately 10−20 seconds and then part ways (not necessarily in the same composition as before the reaction) rather than form a single nucleus.[14][15] If fusion does occur, the temporary merger—termed a compound nucleus—is an excited state. To lose its excitation energy and reach a more stable state, a compound nucleus either fissions or ejects one or several neutrons,[c] which carry away the energy. This occurs in approximately 10−16 seconds after the initial collision.[16][d]

The beam passes through the target and reaches the next chamber, the separator; if a new nucleus is produced, it is carried with this beam.[19] In the separator, the newly produced nucleus is separated from other nuclides (that of the original beam and any other reaction products)[e] and transferred to a surface-barrier detector, which stops the nucleus. The exact location of the upcoming impact on the detector is marked; also marked are its energy and the time of the arrival.[19] The transfer takes about 10−6 seconds; in order to be detected, the nucleus must survive this long.[22] The nucleus is recorded again once its decay is registered, and the location, the energy, and the time of the decay are measured.[19]

Stability of a nucleus is provided by the strong interaction. However, its range is very short; as nuclei become larger, its influence on the outermost nucleons (protons and neutrons) weakens. At the same time, the nucleus is torn apart by electrostatic repulsion between protons, as it has unlimited range.[23] Nuclei of the heaviest elements are thus theoretically predicted[24] and have so far been observed[25] to primarily decay via decay modes that are caused by such repulsion: alpha decay and spontaneous fission;[f] these modes are predominant for nuclei of superheavy elements. Alpha decays are registered by the emitted alpha particles, and the decay products are easy to determine before the actual decay; if such a decay or a series of consecutive decays produces a known nucleus, the original product of a reaction can be determined arithmetically.[g] Spontaneous fission, however, produces various nuclei as products, so the original nuclide cannot be determined from its daughters.[h]

The information available to physicists aiming to synthesize one of the heaviest elements is thus the information collected at the detectors: location, energy, and time of arrival of a particle to the detector, and those of its decay. The physicists analyze this data and seek to conclude that it was indeed caused by a new element and could not have been caused by a different nuclide than the one claimed. Often, provided data is insufficient for a conclusion that a new element was definitely created and there is no other explanation for the observed effects; errors in interpreting data have been made.[i]

History

The city center of Darmstadt, the namesake of darmstadtium

Discovery

Darmstadtium was first created on November 9, 1994, at the Institute for Heavy Ion Research (Gesellschaft für Schwerionenforschung, GSI) in Darmstadt, Germany, by Peter Armbruster and Gottfried Münzenberg, under the direction of Sigurd Hofmann. The team bombarded a lead-208 target with accelerated nuclei of nickel-62 in a heavy ion accelerator and detected a single atom of the isotope darmstadtium-269:[37]

208
82
Pb + 62
28
Ni → 269
110
Ds + 1
0
n

In the same series of experiments, the same team also carried out the reaction using heavier nickel-64 ions. During two runs, 9 atoms of 271Ds were convincingly detected by correlation with known daughter decay properties:[38]

208
82
Pb + 64
28
Ni → 271
110
Ds + 1
0
n

Prior to this, there had been failed synthesis attempts in 1986–87 at the Joint Institute for Nuclear Research in Dubna (then in the Soviet Union) and in 1990 at the GSI. A 1995 attempt at the Lawrence Berkeley National Laboratory resulted in signs suggesting but not pointing conclusively at the discovery of a new isotope 267Ds formed in the bombardment of 209Bi with 59Co, and a similarly inconclusive 1994 attempt at the JINR showed signs of 273Ds being produced from 244Pu and 34S. Each team proposed its own name for element 110: the American team proposed hahnium after Otto Hahn in an attempt to resolve the situation on element 105 (which they had long been suggesting this name for), the Russian team proposed becquerelium after Henri Becquerel, and the German team proposed darmstadtium after Darmstadt, the location of their institute.[39] The IUPAC/IUPAP Joint Working Party (JWP) recognised the GSI team as discoverers in their 2001 report, giving them the right to suggest a name for the element.[40]

Naming

Using Mendeleev's nomenclature for unnamed and undiscovered elements, darmstadtium should be known as eka-platinum. In 1979, IUPAC published recommendations according to which the element was to be called ununnilium (with the corresponding symbol of Uun),[41] a systematic element name as a placeholder, until the element was discovered (and the discovery then confirmed) and a permanent name was decided on. Although widely used in the chemical community on all levels, from chemistry classrooms to advanced textbooks, the recommendations were mostly ignored among scientists in the field, who called it "element 110", with the symbol of E110, (110) or even simply 110.[3]

In 1996, the Russian team proposed the name becquerelium after Henri Becquerel.[42] The American team in 1997 proposed the name hahnium[43] after Otto Hahn (previously this name had been used for element 105).

The name darmstadtium (Ds) was suggested by the GSI team in honor of the city of Darmstadt, where the element was discovered.[44][45] The GSI team originally also considered naming the element wixhausium, after the suburb of Darmstadt known as Wixhausen where the element was discovered, but eventually decided on darmstadtium.[46] Policium had also been proposed as a joke due to the emergency telephone number in Germany being 1-1-0. The new name darmstadtium was officially recommended by IUPAC on August 16, 2003.[44]

Isotopes

List of darmstadtium isotopes
Isotope Half-life[j] Decay
mode
Discovery
year[47]
Discovery
reaction[48]
Value Ref
267Ds[k] 10 µs [47] α 1994 209Bi(59Co,n)
269Ds 230 µs [47] α 1994 208Pb(62Ni,n)
270Ds 205 µs [47] α 2000 207Pb(64Ni,n)
270mDs 10 ms [47] α 2000 207Pb(64Ni,n)
271Ds 90 ms [47] α 1994 208Pb(64Ni,n)
271mDs 1.7 ms [47] α 1994 208Pb(64Ni,n)
273Ds 240 µs [47] α 1996 244Pu(34S,5n)[49]
277Ds 3.5 ms [50] α 2010 285Fl(—,2α)
279Ds 0.21 s [51] SF, α 2003 287Fl(—,2α)
280Ds[52][k] 6.7 ms [53][54] SF 2014 292Lv(—,3α)
281Ds 12.7 s [51] SF, α 2004 289Fl(—,2α)
281mDs[k] 0.9 s [47] α 2012 293mLv(—,3α)

Darmstadtium has no stable or naturally occurring isotopes. Several radioactive isotopes have been synthesized in the laboratory, either by fusing two atoms or by observing the decay of heavier elements. Nine different isotopes of darmstadtium have been reported with atomic masses 267, 269–271, 273, 277, and 279–281, although darmstadtium-267 and darmstadtium-280 are unconfirmed. Three darmstadtium isotopes, darmstadtium-270, darmstadtium-271, and darmstadtium-281, have known metastable states, although that of darmstadtium-281 is unconfirmed.[55] Most of these decay predominantly through alpha decay, but some undergo spontaneous fission.[56]

Stability and half-lives

This chart of decay modes according to the model of the Japan Atomic Energy Agency predicts several superheavy nuclides within the island of stability having total half-lives exceeding one year (circled) and undergoing primarily alpha decay, peaking at 294Ds with an estimated half-life of 300 years.[57]

All darmstadtium isotopes are extremely unstable and radioactive; in general, the heavier isotopes are more stable than the lighter. The most stable known darmstadtium isotope, 281Ds, is also the heaviest known darmstadtium isotope; it has a half-life of 12.7 seconds. The isotope 279Ds has a half-life of 0.18 seconds, while the unconfirmed 281mDs has a half-life of 0.9 seconds. The remaining seven isotopes and two metastable states have half-lives between 1 microsecond and 70 milliseconds.[56] Some unknown darmstadtium isotopes may have longer half-lives, however.[58]

Theoretical calculation in a quantum tunneling model reproduces the experimental alpha decay half-life data for the known darmstadtium isotopes.[59][60] It also predicts that the undiscovered isotope 294Ds, which has a magic number of neutrons (184),[3] would have an alpha decay half-life on the order of 311 years; exactly the same approach predicts a ~3500-year alpha half-life for the non-magic 293Ds isotope, however.[58][61]

Predicted properties

No properties of darmstadtium or its compounds have been measured; this is due to its extremely limited and expensive production[13] and the fact that darmstadtium (and its parents) decays very quickly. Properties of darmstadtium metal remain unknown and only predictions are available.

Chemical

Darmstadtium is the eighth member of the 6d series of transition metals. Since copernicium (element 112) has been shown to be a group 12 metal, it is expected that all the elements from 104 to 111 would continue a fourth transition metal series, with darmstadtium as part of the platinum group metals.[45] Calculations on its ionization potentials and atomic and ionic radii are similar to that of its lighter homologue platinum, thus implying that darmstadtium's basic properties will resemble those of the other group 10 elements, nickel, palladium, and platinum.[3]

Prediction of the probable chemical properties of darmstadtium has not received much attention recently. Darmstadtium should be a very noble metal. The predicted standard reduction potential for the Ds2+/Ds couple is 1.7 V.[3] Based on the most stable oxidation states of the lighter group 10 elements, the most stable oxidation states of darmstadtium are predicted to be the +6, +4, and +2 states; however, the neutral state is predicted to be the most stable in aqueous solutions. In comparison, only palladium and platinum are known to show the maximum oxidation state in the group, +6, while the most stable states are +4 and +2 for both nickel and palladium. It is further expected that the maximum oxidation states of elements from bohrium (element 107) to darmstadtium (element 110) may be stable in the gas phase but not in aqueous solution.[3] Darmstadtium hexafluoride (DsF6) is predicted to have very similar properties to its lighter homologue platinum hexafluoride (PtF6), having very similar electronic structures and ionization potentials.[3][62][63] It is also expected to have the same octahedral molecular geometry as PtF6.[64] Other predicted darmstadtium compounds are darmstadtium carbide (DsC) and darmstadtium tetrachloride (DsCl4), both of which are expected to behave like their lighter homologues.[64] Unlike platinum, which preferentially forms a cyanide complex in its +2 oxidation state, Pt(CN)2, darmstadtium is expected to preferentially remain in its neutral state and form Ds(CN)2−
2
instead, forming a strong Ds–C bond with some multiple bond character.[65]

Physical and atomic

Darmstadtium is expected to be a solid under normal conditions and to crystallize in the body-centered cubic structure, unlike its lighter congeners which crystallize in the face-centered cubic structure, because it is expected to have different electron charge densities from them.[4] It should be a very heavy metal with a density of around 34.8 g/cm3. In comparison, the densest known element that has had its density measured, osmium, has a density of only 22.61 g/cm3.[3] This results from darmstadtium's high atomic weight, the lanthanide and actinide contractions, and relativistic effects, although production of enough darmstadtium to measure this quantity would be impractical, and the sample would quickly decay.[3]

The outer electron configuration of darmstadtium is calculated to be 6d8 7s2, which obeys the Aufbau principle and does not follow platinum's outer electron configuration of 5d9 6s1. This is due to the relativistic stabilization of the 7s2 electron pair over the whole seventh period, so that none of the elements from 104 to 112 are expected to have electron configurations violating the Aufbau principle. The atomic radius of darmstadtium is expected to be around 132 pm.[3]

Experimental chemistry

Unambiguous determination of the chemical characteristics of darmstadtium has yet to have been established[66] due to the short half-lives of darmstadtium isotopes and a limited number of likely volatile compounds that could be studied on a very small scale. One of the few darmstadtium compounds that are likely to be sufficiently volatile is darmstadtium hexafluoride (DsF
6
), as its lighter homologue platinum hexafluoride (PtF
6
) is volatile above 60 °C and therefore the analogous compound of darmstadtium might also be sufficiently volatile;[45] a volatile octafluoride (DsF
8
) might also be possible.[3] For chemical studies to be carried out on a transactinide, at least four atoms must be produced, the half-life of the isotope used must be at least 1 second, and the rate of production must be at least one atom per week.[45] Even though the half-life of 281Ds, the most stable confirmed darmstadtium isotope, is 12.7 seconds, long enough to perform chemical studies, another obstacle is the need to increase the rate of production of darmstadtium isotopes and allow experiments to carry on for weeks or months so that statistically significant results can be obtained. Separation and detection must be carried out continuously to separate out the darmstadtium isotopes and have automated systems experiment on the gas-phase and solution chemistry of darmstadtium, as the yields for heavier elements are predicted to be smaller than those for lighter elements; some of the separation techniques used for bohrium and hassium could be reused. However, the experimental chemistry of darmstadtium has not received as much attention as that of the heavier elements from copernicium to livermorium.[3][66][67]

The more neutron-rich darmstadtium isotopes are the most stable[56] and are thus more promising for chemical studies.[3][45] However, they can only be produced indirectly from the alpha decay of heavier elements,[68][69][70] and indirect synthesis methods are not as favourable for chemical studies as direct synthesis methods.[3] The more neutron-rich isotopes 276Ds and 277Ds might be produced directly in the reaction between thorium-232 and calcium-48, but the yield is expected to be low.[3][71][72] Furthermore, this reaction has already been tested without success,[71] and more recent experiments that have successfully synthesized 277Ds using indirect methods show that it has a short half-life of 3.5 ms, not long enough to perform chemical studies.[50][69] The only known darmstadtium isotope with a half-life long enough for chemical research is 281Ds, which would have to be produced as the granddaughter of 289Fl.[73]

See also

Notes

  1. ^ In nuclear physics, an element is called heavy if its atomic number is high; lead (element 82) is one example of such a heavy element. The term "superheavy elements" typically refers to elements with atomic number greater than 103 (although there are other definitions, such as atomic number greater than 100[8] or 112;[9] sometimes, the term is presented an equivalent to the term "transactinide", which puts an upper limit before the beginning of the hypothetical superactinide series).[10] Terms "heavy isotopes" (of a given element) and "heavy nuclei" mean what could be understood in the common language—isotopes of high mass (for the given element) and nuclei of high mass, respectively.
  2. ^ In 2009, a team at JINR led by Oganessian published results of their attempt to create hassium in a symmetric 136Xe + 136Xe reaction. They failed to observe a single atom in such a reaction, putting the upper limit on the cross section, the measure of probability of a nuclear reaction, as 2.5 pb.[11] In comparison, the reaction that resulted in hassium discovery, 208Pb + 58Fe, had a cross section of ~20 pb (more specifically, 19+19
    −11
     pb), as estimated by the discoverers.[12]
  3. ^ The greater the excitation energy, the more neutrons are ejected. If the excitation energy is lower than energy binding each neutron to the rest of the nucleus, neutrons are not emitted; instead, the compound nucleus de-excites by emitting a gamma ray.[16]
  4. ^ The definition by the IUPAC/IUPAP Joint Working Party states that a chemical element can only be recognized as discovered if a nucleus of it has not decayed within 10−14 seconds. This value was chosen as an estimate of how long it takes a nucleus to acquire its outer electrons and thus display its chemical properties.[17] This figure also marks the generally accepted upper limit for lifetime of a compound nucleus.[18]
  5. ^ This separation is based on that the resulting nuclei move past the target more slowly then the unreacted beam nuclei. The separator contains electric and magnetic fields whose effects on a moving particle cancel out for a specific velocity of a particle.[20] Such separation can also be aided by a time-of-flight measurement and a recoil energy measurement; a combination of the two may allow to estimate the mass of a nucleus.[21]
  6. ^ Not all decay modes are caused by electrostatic repulsion. For example, beta decay is caused by the weak interaction.[26]
  7. ^ Since mass of a nucleus is not measured directly but is rather calculated from that of another nucleus, such measurement is called indirect. Direct measurements are also possible, but for the most part they have remained unavailable for heaviest nuclei.[27] The first direct measurement of mass of a superheavy nucleus was reported in 2018 at LBNL.[28] Mass was determined from the location of a nucleus after the transfer (the location helps determine its trajectory, which is linked to the mass-to-charge ratio of the nucleus, since the transfer was done in presence of a magnet).[29]
  8. ^ Spontaneous fission was discovered by Soviet physicist Georgy Flerov,[30] a leading scientist at JINR, and thus it was a "hobbyhorse" for the facility.[31] In contrast, the LBL scientists believed fission information was not sufficient for a claim of synthesis of an element. They believed spontaneous fission had not been studied enough to use it for identification of a new element, since there was a difficulty of establishing that a compound nucleus had only ejected neutrons and not charged particles like protons or alpha particles.[18] They thus preferred to link new isotopes to the already known ones by successive alpha decays.[30]
  9. ^ For instance, element 102 was mistakenly identified in 1957 at the Nobel Institute of Physics in Stockholm, Stockholm County, Sweden.[32] There were no earlier definitive claims of creation of this element, and the element was assigned a name by its Swedish, American, and British discoverers, nobelium. It was later shown that the identification was incorrect.[33] The following year, RL was unable to reproduce the Swedish results and announced instead their synthesis of the element; that claim was also disproved later.[33] JINR insisted that they were the first to create the element and suggested a name of their own for the new element, joliotium;[34] the Soviet name was also not accepted (JINR later referred to the naming of element 102 as "hasty").[35] The name "nobelium" remained unchanged on account of its widespread usage.[36]
  10. ^ Different sources give different values for half-lives; the most recently published values are listed.
  11. ^ a b c This isotope is unconfirmed

References

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  34. ^ Kragh 2018, p. 40.
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Bibliography

External links

9 November 1953

Cambodia gains independence from France.

Independence Day is a national holiday observed annually in Cambodia every 9 November. The date celebrates Cambodia’s Declaration of Independence from France on 9 November 1953. The site to celebrate the ceremony is at Independence Monument. The vital celebrations are held in the capital city, Phnom Penh although there are some celebrations in many provinces.

France started controlling Cambodia in 1863. After being colonized around 80 years, King Norodom Sihanouk began claiming dependence from France in 1949. In 1953, he was successful to gain full independence, and France agreed to decolonize the whole country. Due to this accomplishment, Cambodian citizens viewed him as “the father of independence, which depicts that he was the hero of the country. He made the country to develop rapidly.

Every year, Independence Day is a very special and happy day for the whole nation. It portrayed the Khmer success over colonization. It is celebrated in many places around the country, and the absolutely crucial one takes place at Independence Monument in Phnom Penh.

On that day, all the leaders and representatives of state organizations and public departments must participate and celebrate the formal ceremony in the morning. Usually the roads around the Independence Monument are closed to provide the space for the ceremony. The whole ceremony is broadcast on national television and radio. Other channels also broadcast it from the National TV. Therefore, the people around the country can watch it.

Every state palace is decorated with some slogans related to the independence of Cambodia, and the lights. At night, there is firework in the Chatomuk River located in front of the Royal Palace. Because it is the holiday, there are a lot of people going out to see that event in front of the Royal Palace and Chroy Changvar area, which is opposite to the Royal Palace.

9 November 1994

The chemical element darmstadtium is discovered.

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Darmstadtium is a synthetic chemical element with symbol Ds and atomic number 110. It is an extremely radioactive synthetic element. The most stable known isotope, darmstadtium-281, has a half-life of approximately 10 seconds. Darmstadtium was first created in 1994 by the GSI Helmholtz Centre for Heavy Ion Research near the city of Darmstadt, Germany, after which it was named.

In the periodic table, it is a d-block transactinide element. It is a member of the 7th period and is placed in the group 10 elements, although no chemical experiments have yet been carried out to confirm that it behaves as the heavier homologue to platinum in group 10 as the eighth member of the 6d series of transition metals. Darmstadtium is calculated to have similar properties to its lighter homologues, nickel, palladium, and platinum.

Darmstadtium was first created on November 9, 1994, at the Institute for Heavy Ion Research in Darmstadt, Germany, by Peter Armbruster and Gottfried Münzenberg, under the direction of Sigurd Hofmann. The team bombarded a lead-208 target with accelerated nuclei of nickel-62 in a heavy ion accelerator and detected a single atom of the isotope darmstadtium.

In the same series of experiments, the same team also carried out the reaction using heavier nickel-64 ions. During two runs, 9 atoms of 271Ds were convincingly detected by correlation with known daughter decay properties.

9 November 1994

darmstadtium-l

The chemical element ‘darmstadtium’ is first discovered.

Darmstadtium was discovered by S. Hofmann, V. Ninov, F. P. Hessberger, P. Armbruster, H. Folger, G. Münzenberg, H. J. Schött, and others in 1994 at Gesellschaft für Schwerionenforschung in Darmstadt, Germany.The name darmstadtium lies within the long established tradition of naming an element after the place of its discovery, Darmstadt, in Germany.

On the 9th of November 1994,the first atom of element 110, darmstadtium, was detected at the Gesellschaft für Schwerionenforschung in Darmstadt, Germany. The isotope discovered has an atomic number of 269 that is 269 times heavier than hydrogen.The new element was produced by fusing a nickel and a lead atom together. This was achieved by accelerating the nickel atoms to a high energy in the heavy ion accelerator UNILAC at GSI. Over a period of many days, many billion billion nickel atoms were fired at a lead target in order to produce and identify a single atom of darmstadtium.