|Pronunciation|| / ,- -/(|
|Mass number||281(most stable isotope)|
|Darmstadtium in the periodic table|
|Atomic number (Z)||110|
|Element category||transition metalUnknown chemical properties, but probably a|
|Electron configuration||[ Rn ] 5f14 6d8 7s2(predicted)|
Electrons per shell
|2, 8, 18, 32, 32, 16, 2(predicted)|
|Phase at STP||solid (predicted)|
|Density (near r.t.)||34.8 g/cm3(predicted)|
|Oxidation states||(0), (+2), (+4), (+6), (+8)(predicted)|
|Atomic radius||empirical:132 pm (predicted)|
|Covalent radius||128 pm(estimated)|
|Crystal structure|| body-centered cubic (bcc)|
|Naming||after Darmstadt, Germany, where it was discovered|
|Discovery||Gesellschaft für Schwerionenforschung (1994)|
|Main isotopes of darmstadtium|
Darmstadtium is a synthetic 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.
A synthetic element is one of 24 chemical elements that do not occur naturally on Earth: they have been created by human manipulation of fundamental particles in a nuclear reactor or particle accelerator, or explosion of an atomic bomb; and thus are called "synthetic", "artificial", or "man-made". The synthetic elements are those with atomic numbers 95–118, as shown in purple on the accompanying periodic table: these 24 elements were created between 1944 and 2010. The mechanism for the creation of a synthetic element is to force additional protons onto the nucleus of an element with an atomic number lower than ninety-five. All synthetic elements are unstable, but they decay at a widely varying rate: their half-lives range from 15.6 million years to a few hundred microseconds.
A chemical element is a species of atom having the same number of protons in their atomic nuclei. For example, the atomic number of oxygen is 8, so the element oxygen consists of all atoms which have 8 protons.
In chemistry, a symbol is an abbreviation for a chemical element. Symbols for chemical elements normally consist of one or two letters from the Latin alphabet and are written with the first letter capitalised.
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.
The periodic table, also known as the periodic table of elements, is a tabular display of the chemical elements, which are arranged by atomic number, electron configuration, and recurring chemical properties. The structure of the table shows periodic trends. The seven rows of the table, called periods, generally have metals on the left and non-metals on the right. The columns, called groups, contain elements with similar chemical behaviours. Six groups have accepted names as well as assigned numbers: for example, group 17 elements are the halogens; and group 18 are the noble gases. Also displayed are four simple rectangular areas or blocks associated with the filling of different atomic orbitals.
A period 7 element is one of the chemical elements in the seventh row of the periodic table of the chemical elements. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behaviour of the elements as their atomic number increases: a new row is begun when chemical behaviour begins to repeat, meaning that elements with similar behaviour fall into the same vertical columns. The seventh period contains 32 elements, tied for the most with period 6, beginning with francium and ending with oganesson, the heaviest element currently discovered. As a rule, period 7 elements fill their 7s shells first, then their 5f, 6d, and 7p shells, in that order; however, there are exceptions, such as uranium.
Group 10, numbered by current IUPAC style, is the group of chemical elements in the periodic table that consists of nickel (Ni), palladium (Pd), platinum (Pt), and perhaps also the chemically uncharacterized darmstadtium (Ds). All are d-block transition metals. All known isotopes of darmstadtium are radioactive with short half-lives, and are not known to occur in nature; only minute quantities have been synthesized in laboratories.
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:
Darmstadt is a city in the state of Hesse in Germany, located in the southern part of the Rhine-Main-Area. Darmstadt had a population of around 157,437 at the end of 2016. The Darmstadt Larger Urban Zone has 430,993 inhabitants.
Germany, officially the Federal Republic of Germany, is a country in Central and Western Europe, lying between the Baltic and North Seas to the north and the Alps, Lake Constance and the High Rhine to the south. It borders Denmark to the north, Poland and the Czech Republic to the east, Austria and Switzerland to the south, France to the southwest, and Luxembourg, Belgium and the Netherlands to the west.
Peter Armbruster is a physicist at the Gesellschaft für Schwerionenforschung (GSI) facility in Darmstadt, Germany, and is credited with co-discovering elements 107 (bohrium), 108 (hassium), 109 (meitnerium), 110 (darmstadtium), 111 (roentgenium), and 112 (copernicium) with research partner Gottfried Münzenberg.
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:
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.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.
Dubna is a town in Moscow Oblast, Russia. It has a status of naukograd, being home to the Joint Institute for Nuclear Research, an international nuclear physics research center and one of the largest scientific foundations in the country. It is also home to MKB Raduga, a defense aerospace company specializing in design and production of missile systems. The modern town was developed in the middle of the 20th century and town status was granted to it in 1956. Population: 70,663 (2010 Census); 60,951 (2002 Census); 65,805 (1989 Census).
The Soviet Union, officially known as the Union of Soviet Socialist Republics (USSR), was a federal sovereign state in northern Eurasia that existed from 1922 to 1991. Nominally a union of multiple national Soviet republics, in practice its government and economy were highly centralized. The country was a one-party state, governed by the Communist Party with Moscow as its capital in its largest republic, the Russian Soviet Federative Socialist Republic. Other major urban centers were Leningrad, Kiev, Minsk, Tashkent, Alma-Ata, and Novosibirsk. It spanned over 10,000 kilometers (6,200 mi) east to west across 11 time zones, and over 7,200 kilometers (4,500 mi) north to south. Its territory included much of Eastern Europe, as well as part of Northern Europe and all of Northern and Central Asia. It had five climate zones: tundra, taiga, steppes, desert and mountains.
Lawrence Berkeley National Laboratory (LBNL), commonly referred to as Berkeley Lab, is a United States national laboratory that conducts scientific research on behalf of the United States Department of Energy (DOE). It is located in the Berkeley Hills near Berkeley, California, overlooking the main campus of the University of California, Berkeley. It is managed and operated by the University of California.
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),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.
Dmitri Mendeleev published a periodic table of the chemical elements in 1869 based on properties that appeared with some regularity as he laid out the elements from lightest to heaviest. When Mendeleev proposed his periodic table, he noted gaps in the table and predicted that as-then-unknown elements existed with properties appropriate to fill those gaps. He named them eka-boron, eka-aluminium and eka-silicon, with respective atomic masses of 44, 68, and 72.
Platinum is a chemical element with the symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Its name is derived from the Spanish term platino, meaning "little silver".
A systematic element name is the temporary name assigned to a newly synthesized or not yet synthesized chemical element. A systematic symbol is also derived from this name. In chemistry, a transuranic element receives a permanent name and symbol only after its synthesis has been confirmed. In some cases, such as the Transfermium Wars, controversies over the formal name and symbol have been protracted and highly political. In order to discuss such elements without ambiguity, the International Union of Pure and Applied Chemistry (IUPAC) uses a set of rules to assign a temporary systematic name and symbol to each such element. This approach to naming originated in the successful development of regular rules for the naming of organic compounds.
In 1996, the Russian team proposed the name becquerelium after Henri Becquerel.The American team in 1997 proposed the name hahnium 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.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. 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.
|279Ds||0.21 s||SF, α||2003||287Fl(—,2α)|
|281Ds||12.7 s||SF, α||2004||289Fl(—,2α)|
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.Most of these decay predominantly through alpha decay, but some undergo spontaneous fission.
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. Some unknown darmstadtium isotopes may have longer half-lives, however.
Theoretical calculation in a quantum tunneling model reproduces the experimental alpha decay half-life data for the known darmstadtium isotopes. years; exactly the same approach predicts a ~3500-year alpha half-life for the non-magic 293Ds isotope, however.It also predicts that the undiscovered isotope 294Ds, which has a magic number of neutrons (184), would have an alpha decay half-life on the order of 311
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.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.
Prediction of the probable chemical properties of darmstadtium has not received much attention recently. Darmstadtium should be the third-most noble metal in the periodic table, even more noble than gold, with a predicted standard reduction potential of 1.7 V for the Ds2+/Ds couple, greater than the value of 1.5 V for the Au3+/Au couple; only roentgenium and copernicium are expected to be more noble than darmstadtium. 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. 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. It is also expected to have the same octahedral molecular geometry as PtF6. Other predicted darmstadtium compounds are darmstadtium carbide (DsC) and darmstadtium tetrachloride (DsCl4), both of which are expected to behave like their lighter homologues. 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.
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. g/cm3. In comparison, the densest known element that has had its density measured, osmium, has a density of only 22.61 g/cm3. 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.It should be a very heavy metal with a density of around 34.8
The outer electron configuration of darmstadtium is calculated to be 6d87s2, which obeys the Aufbau principle and does not follow platinum's outer electron configuration of 5d96s1. 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.
Unambiguous determination of the chemical characteristics of darmstadtium has yet to have been established 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; a volatile octafluoride (DsF
8) might also be possible. 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. 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.
The more neutron-rich darmstadtium isotopes are the most stable ms, not long enough to perform chemical studies. 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.and are thus more promising for chemical studies. However, they can only be produced indirectly from the alpha decay of heavier elements, and indirect synthesis methods are not as favourable for chemical studies as direct synthesis methods. 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. Furthermore, this reaction has already been tested without success, and more recent experiments that have successfully synthesized 277Ds using indirect methods show that it has a short half-life of 3.5
Bohrium is a synthetic chemical element with the symbol Bh and atomic number 107. It is named after Danish physicist Niels Bohr. As a synthetic element, it can be created in a laboratory but is not found in nature. All known isotopes of bohrium are extremely radioactive; the most stable known isotope is 270Bh with a half-life of approximately 61 seconds, though the unconfirmed 278Bh may have a longer half-life of about 690 seconds.
Dubnium is a synthetic chemical element with the symbol Db and atomic number 105. Dubnium is highly radioactive: the most stable known isotope, dubnium-268, has a half-life of about 28 hours. This greatly limits the extent of research on dubnium.
Hassium is a chemical element with the symbol Hs and the atomic number 108. It is not known to occur in nature and has been made only in laboratories in minuscule quantities. Hassium is highly radioactive; the most stable known isotope, 269Hs, has a half-life of approximately 16 seconds.
Meitnerium is a synthetic chemical element with the symbol Mt and atomic number 109. It is an extremely radioactive synthetic element. The most stable known isotope, meitnerium-278, has a half-life of 4.5 seconds, although the unconfirmed meitnerium-282 may have a longer half-life of 67 seconds. The GSI Helmholtz Centre for Heavy Ion Research near Darmstadt, Germany, first created this element in 1982. It is named after Lise Meitner.
Roentgenium is a chemical element with the symbol Rg and atomic number 111. It is an extremely radioactive synthetic element that can be created in a laboratory but is not found in nature. The most stable known isotope, roentgenium-282, has a half-life of 100 seconds, although the unconfirmed roentgenium-286 may have a longer half-life of about 10.7 minutes. Roentgenium was first created in 1994 by the GSI Helmholtz Centre for Heavy Ion Research near Darmstadt, Germany. It is named after the physicist Wilhelm Röntgen, who discovered X-rays.
Livermorium is a synthetic chemical element with the symbol Lv and has an atomic number of 116. It is an extremely radioactive element that has only been created in the laboratory and has not been observed in nature. The element is named after the Lawrence Livermore National Laboratory in the United States, which collaborated with the Joint Institute for Nuclear Research (JINR) in Dubna, Russia to discover livermorium during experiments made between 2000 and 2006. The name of the laboratory refers to the city of Livermore, California where it is located, which in turn was named after the rancher and landowner Robert Livermore. The name was adopted by IUPAC on May 30, 2012. Four isotopes of livermorium are known, with mass numbers between 290 and 293 inclusive; the longest-lived among them is livermorium-293 with a half-life of about 60 milliseconds. A fifth possible isotope with mass number 294 has been reported but not yet confirmed.
Unbinilium, also known as eka-radium or simply element 120, is the hypothetical chemical element in the periodic table with symbol Ubn and atomic number 120. Unbinilium and Ubn are the temporary systematic IUPAC name and symbol, which are used until the element is discovered, confirmed, and a permanent name is decided upon. In the periodic table of the elements, it is expected to be an s-block element, an alkaline earth metal, and the second element in the eighth period. It has attracted attention because of some predictions that it may be in the island of stability, although newer calculations expect the island to actually occur at a slightly lower atomic number, closer to copernicium and flerovium.
Ununennium, also known as eka-francium or element 119, is the hypothetical chemical element with symbol Uue and atomic number 119. Ununennium and Uue are the temporary systematic IUPAC name and symbol respectively, which are used until the element is discovered, confirmed, and a permanent name is decided upon. In the periodic table of the elements, it is expected to be an s-block element, an alkali metal, and the first element in the eighth period. It is the lightest element that has not yet been synthesized.
Moscovium is a synthetic chemical element with the symbol Mc and atomic number 115. It was first synthesized in 2003 by a joint team of Russian and American scientists at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia. In December 2015, it was recognized as one of four new elements by the Joint Working Party of international scientific bodies IUPAC and IUPAP. On 28 November 2016, it was officially named after the Moscow Oblast, in which the JINR is situated.
Copernicium is a synthetic chemical element with the symbol Cn and atomic number 112. Its known isotopes are extremely radioactive, and have only been created in a laboratory. The most stable known isotope, copernicium-285, has a half-life of approximately 28 seconds. Copernicium was first created in 1996 by the GSI Helmholtz Centre for Heavy Ion Research near Darmstadt, Germany. It is named after the astronomer Nicolaus Copernicus.
An extended periodic table theorizes about chemical elements beyond those currently known in the periodic table and proven up through oganesson, which completes the seventh period (row) in the periodic table at atomic number (Z) 118.
Flerovium is a superheavy artificial chemical element with the symbol Fl and atomic number 114. It is an extremely radioactive synthetic element. The element is named after the Flerov Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research in Dubna, Russia, where the element was discovered in 1998. The name of the laboratory, in turn, honours the Russian physicist Georgy Flyorov. The name was adopted by IUPAC on 30 May 2012.
Nihonium is a synthetic chemical element with the symbol Nh and atomic number 113. It is extremely radioactive; its most stable known isotope, nihonium-286, has a half-life of about 10 seconds. In the periodic table, nihonium is a transactinide element in the p-block. It is a member of period 7 and group 13.
Unbibium, also known as element 122 or eka-thorium, is the hypothetical chemical element in the periodic table with the placeholder symbol of Ubb and atomic number 122. Unbibium and Ubb are the temporary systematic IUPAC name and symbol respectively, which are used until the element is discovered, confirmed, and a permanent name is decided upon. In the periodic table of the elements, it is expected to follow unbiunium as the second element of the superactinides and the fourth element of the 8th period. Similarly to unbiunium, it is expected to fall within the range of the island of stability, potentially conferring additional stability on some isotopes, especially 306Ubb which is expected to have a magic number of neutrons (184).
Seaborgium (106Sg) is a synthetic element and so has no stable isotopes. A standard atomic weight cannot be given. The first isotope to be synthesized was 263mSg in 1974. There are 12 known radioisotopes from 258Sg to 271Sg and 2 known isomers. The longest-lived isotope is 269Sg with a half-life of 14 minutes.
Hassium (108Hs) is a synthetic element, and thus a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first isotope to be synthesized was 265Hs in 1984. There are 12 known isotopes from 263Hs to 277Hs and 1–4 isomers. The longest-lived isotope is 269Hs with a half-life of 16 seconds.
Darmstadtium (110Ds) is a synthetic element, and thus a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first isotope to be synthesized was 269Ds in 1994. There are 9 known radioisotopes from 267Ds to 281Ds and 2 or 3 known isomers. The longest-lived isotope is 281Ds with a half-life of 9.6 seconds.
Copernicium (112Cn) is a synthetic element, and thus a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first isotope to be synthesized was 277Cn in 1996. There are 6 known radioisotopes ; the longest-lived isotope is 285Cn with a half-life of 29 seconds.
Flerovium (114Fl) is a synthetic element, and thus a standard atomic weight cannot be given. Like all synthetic elements, it has no stable isotopes. The first isotope to be synthesized was 289Fl in 1999. Flerovium has seven known isotopes, and possibly 2 nuclear isomers. The longest-lived isotope is 289Fl with a half-life of 1.9 seconds, but the unconfirmed 290Fl may have a longer half-life of 19 seconds.
Livermorium (116Lv) is an artificial element, and thus a standard atomic weight cannot be given. Like all artificial elements, it has no stable isotopes. The first isotope to be synthesized was 293Lv in 2000. There are four known radioisotopes from 290Lv to 293Lv, as well as a few suggestive indications of a possible heavier isotope 294Lv. The longest-lived of the four well-characterised isotopes is 293Lv with a half-life of 53 ms.