Darmstadtium
Encyclopedia
Darmstadtium is a chemical element
with the symbol Ds and atomic number
110. It is placed as the heaviest member of group 10, but no known isotope is sufficiently stable to allow chemical experiments to confirm its placing in that group. This synthetic element
is one of the so-called super-heavy atoms and was first synthesized in 1994, at a facility near the city of Darmstadt
, Germany, from which it takes its name. The longest-lived and heaviest isotope known is 281aDs with a half-life
of ~10 s although a possible nuclear isomer
, 281bDs has an unconfirmed half-life
of about 4 minutes.
(GSI) in Darmstadt
, Germany
, by Peter Armbruster
and Gottfried Münzenberg
, under the direction of professor Sigurd Hofmann. Four atom
s of it were detected by a nuclear fusion
reaction caused by bombarding a lead-208 target with nickel-62 ions:
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:
The IUPAC/IUPAP Joint Working Party (JWP) recognised the GSI team as discoverers in their 2001 report.
and not the suburb Wixhausen
itself. The new name was officially recommended by IUPAC on August 16, 2003. The name was approved on November 4, 2011.
The team at the HIRFL, Lanzhou
, China
, are planning to restudy the reaction after recent calculations indicated a measurable yield in the 4n evaporation channel, leading to the new nuclide .
At the FLNR, scientists will study the new reaction in order to compare the yield with that obtained using projectiles in order to ascertain the viability of using projectiles in SHE synthesis.
This reaction was first studied by scientists at GSI in 1986, without success. A cross section limit of 12 picobarns
(pb) was calculated.
After an upgrade of their facilities, they successfully detected 9 atoms of 271Ds in two runs in 1994 as part of their discovery experiments on element 110.
This reaction was successfully repeated in 2000 by GSI (4 atoms), in 2000
and 2004
by LBNL (9 atoms in total) and in 2002 by RIKEN
(14 atoms). The summation of the data allowed a measurement of the 1n neutron evaporation excitation function.
In addition to the official discovery reactions, in October–November 2000, the team at GSI also studied the reaction using a Pb-207 target in order to search for the new isotope 270Ds. They succeeded in synthesising 8 atoms of 270Ds, relating to a ground state isomer, 270gDs, and a high-spin K-isomer, 270mDs.
The GSI team studied this reaction in 1994 as part of their discovery experiment. Three atoms of 269Ds were detected. A fourth decay chain was measured but subsequently retracted.
This reaction was first studied by the team at Dubna in 1986. They were unable to detect any product atoms and measured a cross section limit of 1 pb.
In 1995, the team at LBNL reported that they had succeeded in detecting a single atom of 267Ds from the 1n neutron evaporation channel. However, several decays were missed and further research is required to confirm this discovery.
The synthesis of darmstadtium by hot fusion pathways was first attempted in 1986 by the team at Dubna. Using the method of detection of spontaneous fission
, they were unable to measure any SF activities and calculated a cross section limit of 1 pb for the decay mode.
In three separate experiments between November 1997 and October 1998, the same team re-studied this reaction as part of their new 48Ca program on the synthesis of superheavy elements.
Several SF activities with relatively long half-lives were detected and tentatively assigned to decay of the daughters 269Sg or 265Rf, with a cross section of 5 pb. These observations have not been confirmed and the results are taken as only an indication for the synthesis of darmstadtium in this reaction.
This reaction was attempted in 1986 and 1987 by the Dubna team. In both experiments, a 10 ms SF activities was measured and assigned to 272Ds, with a calculated cross section of 10 pb. This activity is currently not thought to be due to a darmstadtium isotope.
This reaction was first attempted by the Dubna team in 1987. Only spontaneous fission from the transfer products 240mfAm and 242mfAm were observed and the team calculated a cross section limit of 1.6 pb.
The team at GSI first studied this reaction in 1990. Once again, no atoms of darmstadtium could be detected. In August 2001, the GSI repeated reaction, without success, and calculated a cross section limit of 1.0 pb.
This reaction was first attempted by the Dubna team in 1987. No spontaneous fission was observed.
This reaction was first attempted by the Dubna team in 1987. No spontaneous fission was observed.
It was further studied in 1990 by the GSI team. Once again, no atoms were detected and a cross section limit of 21 pb was calculated.
This reaction was first studied in 1990 by the GSI team. No atoms were detected and a cross section limit of 21 pb was calculated.
In September 1994 the team at Dubna detected a single atom of 273Ds, formed in the 5n neutron evaporation channel. The measured cross section was just 400 femtobarns (fb).
In some experiments, the decay of 293Uuh and 289Uuq produced an isotope of darmstadtium decaying by emission of an 8.77 MeV alpha particle with a half-life of 3.7 minutes. Although unconfirmed, it is highly possible that this activity is associated with a meta-stable isomer, namely 281mDs.
The first synthesis of element 114 resulted in two atoms assigned to 288Uuq, decaying to the 280Ds which underwent spontaneous fission
. The assignment was later changed to 289Uuq and the darmstadtium isotope to 281Ds. Hence, 280Ds is currently unknown.
In the claimed synthesis of 293Uuo in 1999, the isotope 277Ds was identified as decaying by 10.18 MeV alpha emission with a half-life of 3.0 ms. This claim was retracted in 2001. This isotope was finally created in 2010 and its decay data supported the fabrication of previous data.
In the synthesis of 277Cn in 1996 by GSI (see copernicium), one decay chain proceeded via 273Ds which decayed by emission of a 9.73 MeV alpha particle with a lifetime of 170 ms. This would have been assigned to an isomeric level. This data could not be confirmed and thus this isotope is currently unknown or unconfirmed.
In the first attempt to synthesize darmstadtium, a 10 ms SF activity was assigned to 272Ds in the reaction 232Th(44Ca,4n). Given current understanding regarding stability, this isotope has been retracted from the Table of Isotopes.
DNS = Di-nuclear system; σ = cross section
, palladium
and platinum
. The highest confirmed oxidation state of +6 is shown by platinum whilst the +4 state is stable for both elements. Both elements also possess a stable +2 state. Darmstadtium is therefore predicted to show oxidation states +6, +4, and +2.
Like other Group 10 elements, darmstadtium can be expected to have notable hardness and catalytic properties.
Chemical element
A chemical element is a pure chemical substance consisting of one type of atom distinguished by its atomic number, which is the number of protons in its nucleus. Familiar examples of elements include carbon, oxygen, aluminum, iron, copper, gold, mercury, and lead.As of November 2011, 118 elements...
with the symbol Ds and atomic number
Atomic number
In chemistry and physics, the atomic number is the number of protons found in the nucleus of an atom and therefore identical to the charge number of the nucleus. It is conventionally represented by the symbol Z. The atomic number uniquely identifies a chemical element...
110. It is placed as the heaviest member of group 10, but no known isotope is sufficiently stable to allow chemical experiments to confirm its placing in that group. This synthetic element
Synthetic element
In chemistry, a synthetic element is a chemical element that is too unstable to occur naturally on Earth, and therefore has to be created artificially. So far 30 synthetic elements have been discovered—that is, synthesized...
is one of the so-called super-heavy atoms and was first synthesized in 1994, at a facility near the city of Darmstadt
Darmstadt
Darmstadt is a city in the Bundesland of Hesse in Germany, located in the southern part of the Rhine Main Area.The sandy soils in the Darmstadt area, ill-suited for agriculture in times before industrial fertilisation, prevented any larger settlement from developing, until the city became the seat...
, Germany, from which it takes its name. The longest-lived and heaviest isotope known is 281aDs with a half-life
Half-life
Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...
of ~10 s although a possible nuclear isomer
Nuclear isomer
A nuclear isomer is a metastable state of an atomic nucleus caused by the excitation of one or more of its nucleons . "Metastable" refers to the fact that these excited states have half-lives more than 100 to 1000 times the half-lives of the other possible excited nuclear states...
, 281bDs has an unconfirmed half-life
Half-life
Half-life, abbreviated t½, is the period of time it takes for the amount of a substance undergoing decay to decrease by half. The name was originally used to describe a characteristic of unstable atoms , but it may apply to any quantity which follows a set-rate decay.The original term, dating to...
of about 4 minutes.
Official discovery
Darmstadtium was first created on November 9, 1994, at the Gesellschaft für SchwerionenforschungGesellschaft für Schwerionenforschung
The GSI Helmholtz Centre for Heavy Ion Research GmbH in the Wixhausen suburb of Darmstadt, Germany is a federally and state co-funded heavy ion research center. The current director of GSI is Horst Stöcker who succeeded Walter F...
(GSI) in Darmstadt
Darmstadt
Darmstadt is a city in the Bundesland of Hesse in Germany, located in the southern part of the Rhine Main Area.The sandy soils in the Darmstadt area, ill-suited for agriculture in times before industrial fertilisation, prevented any larger settlement from developing, until the city became the seat...
, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
, by Peter Armbruster
Peter Armbruster
Peter Armbruster is a physicist at the Gesellschaft für Schwerionenforschung facility in Darmstadt, Germany, and is credited with co-discovering elements 107 , 108 , 109 , 110 , 111 , and 112 with research partner Gottfried Münzenberg.He studied physics at the Technical...
and Gottfried Münzenberg
Gottfried Münzenberg
Gottfried Münzenberg is a German physicist.He studied physics at Justus-Liebig-Universität in Giessen and Leopold-Franzens-Universität Innsbruck and completed his studies with a Ph.D. at the University of Giessen, Germany, in 1971...
, under the direction of professor Sigurd Hofmann. Four atom
Atom
The atom is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons...
s of it were detected by a nuclear fusion
Nuclear fusion
Nuclear fusion is the process by which two or more atomic nuclei join together, or "fuse", to form a single heavier nucleus. This is usually accompanied by the release or absorption of large quantities of energy...
reaction caused by bombarding a lead-208 target with nickel-62 ions:
- Pb + Ni → Ds + 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:
- Pb + Ni → Ds + n
The IUPAC/IUPAP Joint Working Party (JWP) recognised the GSI team as discoverers in their 2001 report.
Naming
Darmstadtium was first given the temporary name ununnilium (/ˌuːnəˈnɪliəm/ or /ˌʌnəˈnɪliəm/, symbol Uun). Once recognized as discoverers, the team at GSI considered the names darmstadtium (Ds) and wixhausium (Wi) for element 110. They decided on the former and named the element after the city near the place of its discovery, DarmstadtDarmstadt
Darmstadt is a city in the Bundesland of Hesse in Germany, located in the southern part of the Rhine Main Area.The sandy soils in the Darmstadt area, ill-suited for agriculture in times before industrial fertilisation, prevented any larger settlement from developing, until the city became the seat...
and not the suburb Wixhausen
Wixhausen
Wixhausen is a village in southern Hesse, Germany. Covering an area of 23.247 km², in 2006 it had 5,772 inhabitants and 1,310 houses. It is considered the northernmost suburb of the district-free city of Darmstadt. Its main claim to fame is the GSI heavy-ion research laboratory located...
itself. The new name was officially recommended by IUPAC on August 16, 2003. The name was approved on November 4, 2011.
Future experiments
The team at GSI has scheduled experiments for August 27 to October 10, 2010, in order to re-study the K-isomer of formed in the reaction (.The team at the HIRFL, Lanzhou
Lanzhou
Lanzhou is the capital and largest city of Gansu Province in Northwest China. A prefecture-level city, it is a key regional transportation hub, allowing areas further west to maintain railroad connections to the eastern half of the country....
, China
People's Republic of China
China , officially the People's Republic of China , is the most populous country in the world, with over 1.3 billion citizens. Located in East Asia, the country covers approximately 9.6 million square kilometres...
, are planning to restudy the reaction after recent calculations indicated a measurable yield in the 4n evaporation channel, leading to the new nuclide .
At the FLNR, scientists will study the new reaction in order to compare the yield with that obtained using projectiles in order to ascertain the viability of using projectiles in SHE synthesis.
Target-Projectile Combinations leading to Z=110 compound nuclei
The below table contains various combinations of targets and projectiles which could be used to form compound nuclei with Z=110.| Target | Projectile | CN | Attempt result |
|---|---|---|---|
| 208Pb | 64Ni | 272Ds | |
| 208Pb | 62Ni | 270Ds | |
| 232Th | 48Ca | 280Ds | |
| 238U | 40Ar | 278Ds | |
| 244Pu | 36S | 280Ds | |
| 244Pu | 34S | 278Ds | |
| 248Cm | 30Si | 278Ds | |
| 249Cf | 26Mg | 275Ds |
Cold fusion
This section deals with the synthesis of nuclei of darmstadtium by so-called "cold" fusion reactions. These are processes which create compound nuclei at low excitation energy (~10-20 MeV, hence "cold"), leading to a higher probability of survival from fission. The excited nucleus then decays to the ground state via the emission of one or two neutrons only.208Pb(64Ni,xn)272-xDs (x=1)
This reaction was first studied by scientists at GSI in 1986, without success. A cross section limit of 12 picobarns
Barn (unit)
A barn is a unit of area. Originally used in nuclear physics for expressing the cross sectional area of nuclei and nuclear reactions, today it is used in all fields of high energy physics to express the cross sections of any scattering process, and is best understood as a measure of the...
(pb) was calculated.
After an upgrade of their facilities, they successfully detected 9 atoms of 271Ds in two runs in 1994 as part of their discovery experiments on element 110.
This reaction was successfully repeated in 2000 by GSI (4 atoms), in 2000
and 2004
by LBNL (9 atoms in total) and in 2002 by RIKEN
RIKEN
is a large natural sciences research institute in Japan. Founded in 1917, it now has approximately 3000 scientists on seven campuses across Japan, the main one in Wako, just outside Tokyo...
(14 atoms). The summation of the data allowed a measurement of the 1n neutron evaporation excitation function.
207Pb(64Ni,xn)271-xDs (x=1)
In addition to the official discovery reactions, in October–November 2000, the team at GSI also studied the reaction using a Pb-207 target in order to search for the new isotope 270Ds. They succeeded in synthesising 8 atoms of 270Ds, relating to a ground state isomer, 270gDs, and a high-spin K-isomer, 270mDs.
208Pb(62Ni,xn)270-xDs (x=1)
The GSI team studied this reaction in 1994 as part of their discovery experiment. Three atoms of 269Ds were detected. A fourth decay chain was measured but subsequently retracted.
209Bi(59Co,xn)268-xDs
This reaction was first studied by the team at Dubna in 1986. They were unable to detect any product atoms and measured a cross section limit of 1 pb.
In 1995, the team at LBNL reported that they had succeeded in detecting a single atom of 267Ds from the 1n neutron evaporation channel. However, several decays were missed and further research is required to confirm this discovery.
Hot fusion
This section deals with the synthesis of nuclei of darmstadtium by so-called "hot" fusion reactions. These are processes which create compound nuclei at high excitation energy (~40-50 MeV, hence "hot"), leading to a reduced probability of survival from fission. The excited nucleus then decays to the ground state via the emission of 3-5 neutrons. Fusion reactions utilizing 48Ca nuclei usually produce compound nuclei with intermediate excitation energies (~30-35 MeV) and are sometimes referred to as "warm" fusion reactions. This leads, in part, to relatively high yields from these reactions.232Th(48Ca,xn)280-xDs
The synthesis of darmstadtium by hot fusion pathways was first attempted in 1986 by the team at Dubna. Using the method of detection of spontaneous fission
Spontaneous fission
Spontaneous fission is a form of radioactive decay characteristic of very heavy isotopes. Because the nuclear binding energy reaches a maximum at a nuclear mass greater than about 60 atomic mass units , spontaneous breakdown into smaller nuclei and single particles becomes possible at heavier masses...
, they were unable to measure any SF activities and calculated a cross section limit of 1 pb for the decay mode.
In three separate experiments between November 1997 and October 1998, the same team re-studied this reaction as part of their new 48Ca program on the synthesis of superheavy elements.
Several SF activities with relatively long half-lives were detected and tentatively assigned to decay of the daughters 269Sg or 265Rf, with a cross section of 5 pb. These observations have not been confirmed and the results are taken as only an indication for the synthesis of darmstadtium in this reaction.
232Th(44Ca,xn)276-xDs
This reaction was attempted in 1986 and 1987 by the Dubna team. In both experiments, a 10 ms SF activities was measured and assigned to 272Ds, with a calculated cross section of 10 pb. This activity is currently not thought to be due to a darmstadtium isotope.
238U(40Ar,xn)278-xDs
This reaction was first attempted by the Dubna team in 1987. Only spontaneous fission from the transfer products 240mfAm and 242mfAm were observed and the team calculated a cross section limit of 1.6 pb.
The team at GSI first studied this reaction in 1990. Once again, no atoms of darmstadtium could be detected. In August 2001, the GSI repeated reaction, without success, and calculated a cross section limit of 1.0 pb.
236U(40Ar,xn)276-xDs
This reaction was first attempted by the Dubna team in 1987. No spontaneous fission was observed.
235U(40Ar,xn)275-xDs
This reaction was first attempted by the Dubna team in 1987. No spontaneous fission was observed.
It was further studied in 1990 by the GSI team. Once again, no atoms were detected and a cross section limit of 21 pb was calculated.
233U(40Ar,xn)273-xDs
This reaction was first studied in 1990 by the GSI team. No atoms were detected and a cross section limit of 21 pb was calculated.
244Pu(34S,xn)278-xDs (x=5)
In September 1994 the team at Dubna detected a single atom of 273Ds, formed in the 5n neutron evaporation channel. The measured cross section was just 400 femtobarns (fb).
As a decay product
Isotopes of darmstadtium have also been detected in the decay of heavier elements. Observations to date are shown in the table below:| Evaporation Residue | Observed Ds isotope |
|---|---|
| 293Uuh, 289Uuq | 281Ds |
| 291Uuh, 287Uuq, 283Cn | 279Ds |
| 285Uuq | 277Ds |
| 277Cn | 273Ds |
In some experiments, the decay of 293Uuh and 289Uuq produced an isotope of darmstadtium decaying by emission of an 8.77 MeV alpha particle with a half-life of 3.7 minutes. Although unconfirmed, it is highly possible that this activity is associated with a meta-stable isomer, namely 281mDs.
280Ds
The first synthesis of element 114 resulted in two atoms assigned to 288Uuq, decaying to the 280Ds which underwent spontaneous fission
Spontaneous fission
Spontaneous fission is a form of radioactive decay characteristic of very heavy isotopes. Because the nuclear binding energy reaches a maximum at a nuclear mass greater than about 60 atomic mass units , spontaneous breakdown into smaller nuclei and single particles becomes possible at heavier masses...
. The assignment was later changed to 289Uuq and the darmstadtium isotope to 281Ds. Hence, 280Ds is currently unknown.
277Ds
In the claimed synthesis of 293Uuo in 1999, the isotope 277Ds was identified as decaying by 10.18 MeV alpha emission with a half-life of 3.0 ms. This claim was retracted in 2001. This isotope was finally created in 2010 and its decay data supported the fabrication of previous data.
273mDs
In the synthesis of 277Cn in 1996 by GSI (see copernicium), one decay chain proceeded via 273Ds which decayed by emission of a 9.73 MeV alpha particle with a lifetime of 170 ms. This would have been assigned to an isomeric level. This data could not be confirmed and thus this isotope is currently unknown or unconfirmed.
272Ds
In the first attempt to synthesize darmstadtium, a 10 ms SF activity was assigned to 272Ds in the reaction 232Th(44Ca,4n). Given current understanding regarding stability, this isotope has been retracted from the Table of Isotopes.
Chronology of isotope discovery
| Isotope | Year discovered | Discovery reaction |
|---|---|---|
| 267Ds ?? | 1994 | 209Bi(59Co,n) |
| 268Ds | unknown | |
| 269Ds | 1994 | 208Pb(62Ni,n) |
| 270Dsg,m | 2000 | 207Pb(64Ni,n) |
| 271Dsg,m | 1994 | 208Pb(64Ni,n) |
| 272Ds | unknown | |
| 273Ds | 1996 | 244Pu(34S,5n) |
| 274Ds | unknown | |
| 275Ds | unknown | |
| 276Ds | unknown | |
| 277Ds | 2010 | 242Pu(48Ca,5n) |
| 278Ds | unknown | |
| 279Ds | 2002 | 244Pu(48Ca,5n) |
| 280Ds | unknown | |
| 281aDs | 1999 | 244Pu(48Ca,3n) |
| 281bDs ? | 1999 | 244Pu(48Ca,3n) |
281Ds
The production of 281Ds by the decay of 289Uuq or 293Uuh has produced two very conflicting decay modes. The most common and readily confirmed mode is SF with a half-life of 11 s. A much rarer and hitherto unconfirmed mode is alpha decay by emission of an 8.77 MeV alpha particle with an observed half-life of ~3.7 m. This decay is associated with a unique decay pathway from the parent nuclides and must be assigned to an isomeric level. The half-life suggests that it must be assigned to an isomeric state but further research is required to confirm these reports.271Ds
Decay data from the direct synthesis of 271Ds clearly indicates the presence of two alpha groups. The first has alpha lines at 10.74 and 10.69 MeV with a half-life of 1.63 ms. The other has a single alpha line at 10.71 MeV with a half-life of 69 ms. The first has been assigned to the ground state and the latter to an isomeric level. It has been suggested that the closeness of the alpha decay energies indicates that the isomeric level may decay primarily by delayed gamma emission to the ground state, resulting in an identical measured alpha energy and a combined half-life for the two processes.270Ds
The direct production of 270Ds has clearly identified two alpha groups belonging to two isomeric levels. The ground state decays into the ground state of 266Hs by emitting an 11.03 MeV alpha particle with a half-life of 0.10 ms. The isomeric level decays by alpha emission with alpha lines at 12.15,11.15 and 10.95 MeV with a half-life of 6 ms. The 12.15 MeV has been assigned as decay into the ground state of 266Hs indicating that this high spin K-isomer lies at 1.12 MeV above the ground state.270Ds
Cold fusion
The table below provides cross-sections and excitation energies for cold fusion reactions producing darmstadtium isotopes directly. Data in bold represent maxima derived from excitation function measurements. + represents an observed exit channel.| Projectile | Target | CN | 1n | 2n | 3n |
|---|---|---|---|---|---|
| 62Ni | 208Pb | 270Ds | 3.5 pb | ||
| 64Ni | 208Pb | 272Ds | 15 pb, 9.9 MeV |
Fission of compound nuclei with Z=110
Experiments have been performed in 2004 at the Flerov Laboratory of Nuclear Reactions in Dubna studying the fission characteristics of the compound nucleus 280Ds. The nuclear reaction used is 232Th+48Ca. The result revealed how nuclei such as this fission predominantly by expelling closed shell nuclei such as 132Sn (Z=50, N=82).Decay characteristics
Theoretical calculation in a quantum tunneling model reproduces the experimental alpha decay half live data. It also predicts that the isotope 294110 would have alpha decay half-life of the order of 311 years.Evaporation residue cross sections
The below table contains various targets-projectile combinations for which calculations have provided estimates for cross section yields from various neutron evaporation channels. The channel with the highest expected yield is given.DNS = Di-nuclear system; σ = cross section
| Target | Projectile | CN | Channel (product) | σmax | Model | Ref |
|---|---|---|---|---|---|---|
| 208Pb | 64Ni | 272Ds | 1n (271Ds) | 10 pb | DNS | |
| 232Th | 48Ca | 280Ds | 4n (276Ds) | 0.2 pb | DNS | |
| 230Th | 48Ca | 278Ds | 4n (274Ds) | 1 pb | DNS | |
| 238U | 40Ar | 278Ds | 4n (274Ds) | 2 pb | DNS |
Oxidation states
Darmstadtium is projected to be the eighth member of the 6d series of transition metals and the heaviest member of group 10 in the Periodic Table, below nickelNickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...
, palladium
Palladium
Palladium is a chemical element with the chemical symbol Pd and an atomic number of 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired...
and platinum
Platinum
Platinum is a chemical element with the chemical symbol Pt and an atomic number of 78. Its name is derived from the Spanish term platina del Pinto, which is literally translated into "little silver of the Pinto River." It is a dense, malleable, ductile, precious, gray-white transition metal...
. The highest confirmed oxidation state of +6 is shown by platinum whilst the +4 state is stable for both elements. Both elements also possess a stable +2 state. Darmstadtium is therefore predicted to show oxidation states +6, +4, and +2.
Chemistry
High oxidation states are expected to become more stable as the group is descended, so darmstadtium is expected to form a stable hexafluoride, DsF6, in addition to DsF5 and DsF4. Halogenation should result in the formation of the tetrahalides, DsCl4, DsBr4, and DsI4.Like other Group 10 elements, darmstadtium can be expected to have notable hardness and catalytic properties.