Editing Period 7 element

{{Short description|Any element in row 7 of the periodic table}}
{{Periodic table (micro)| title=Period 7 in the [[periodic table]] | mark=Fr,Ra,Ac,Th,Pa,U,Np,Pu,Am,Cm,Bk,Cf,Es,Fm,Md,No,Lr,Rf,Db,Sg,Bh,Hs,Mt,Ds,Rg,Cn,Nh,Fl,Mc,Lv,Ts,Og}}
{{Sidebar periodic table|expanded=structure }}
A '''period 7 element''' is one of the [[chemical element]]s in the seventh row (or [[Periodic table period|period]]) of the [[periodic table|periodic table of the chemical elements]]. The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behavior of the elements as their atomic number increases: a new row is begun when chemical behavior begins to repeat, meaning that elements with similar behavior fall into the same vertical columns. The seventh period contains 32 elements, tied for the most with [[Period 6 element|period 6]], beginning with [[francium]] and ending with [[oganesson]], the heaviest element currently discovered. As a rule, period 7 elements fill their 7s [[electron shell|shells]] first, then their 5f, 6d, and 7p shells in that order, but there are exceptions, such as [[uranium]].

==Properties==

All period 7 elements are [[radioactive]]. This period contains the [[actinides]], which include [[plutonium]], the last naturally occurring element;<ref>{{Cite web |title=Periodic Table – Royal Society of Chemistry |url=https://www.rsc.org/periodic-table/ |access-date=2023-10-19 |website=www.rsc.org}}</ref>{{refn | group = note | Trace quantities of <sup>239</sup>Pu are found in uranium deposits<ref>{{Cite book |last1=Miner |first1=William N. |title=The Encyclopedia of the Chemical Elements |last2=Schonfeld, Fred W. |publisher=Reinhold Book Corporation |year=1968 |editor-last=Clifford A. Hampel |location=New York (NY) |pages=[https://archive.org/details/encyclopediaofch00hamp/page/541 541] |chapter=Plutonium |lccn=68029938 |ref=CITEREFMiner1968 |chapter-url=https://archive.org/details/encyclopediaofch00hamp |chapter-url-access=registration}}</ref> due to [[neutron capture]] of {{sup|238}}U and subsequent [[beta decay]]. It is also possible that the long-lived isotope {{sup|244}}Pu [[Plutonium-244#Natural_occurrence|may exist primordially]].<ref>{{cite journal |last1=Wu |first1=Yang |last2=Dai |first2=Xiongxin |first3=Shan |last3=Xing |first4=Maoyi |last4=Luo |first5=Marcus |last5=Christl |first6=Hans-Arno |last6=Synal |first7=Shaochun |last7=Hou |date=2022 |title=Direct search for primordial {{sup|244}}Pu in Bayan Obo bastnaesite |url=http://www.ccspublishing.org.cn/article/doi/10.1016/j.cclet.2022.03.036?pageType=en |journal=Chinese Chemical Letters |volume=33 |issue=7 |pages=3522–3526 |doi=10.1016/j.cclet.2022.03.036 |access-date=29 January 2024|url-access=subscription }}</ref>}} subsequent elements must be created artificially. While the first five of these [[synthetic element]]s ([[americium]] through [[einsteinium]]) are now available in [[macroscopic]] quantities, most are extremely rare, having only been prepared in [[microgram]] amounts or less. The later [[transactinide]] elements have only been identified in laboratories in batches of a few atoms at a time.

Though the rarity of many of these elements means that experimental results are not many, their periodic and group trends are less well defined than other periods. Whilst [[francium]] and [[radium]] do show typical properties of their respective groups, [[actinides]] display a much greater variety of behavior and oxidation states than the [[lanthanides]]. These peculiarities are due to a variety of factors, including a large degree of [[spin–orbit coupling]] and relativistic effects, ultimately caused by the very high electric charge of their massive [[atomic nucleus|nuclei]]. Periodicity mostly holds throughout the 6d series and is predicted also for [[moscovium]] and [[livermorium]], but the other four 7p elements, [[nihonium]], [[flerovium]], [[tennessine]], and [[oganesson]], are predicted to have very different properties from those expected for their groups.

==Elements==
:{| class="wikitable sortable"
! colspan="3" | [[Chemical element]]
! [[Block (periodic table)|Block]]
! [[Electron configuration]]
! Occurrence
|-
! &nbsp;
!
!
!
!
!
|- bgcolor="{{element color|s-block}}"
|| 87  || '''Fr''' || [[Francium]] || [[s-block]] || [Rn] 7s<sup>1</sup> || [[Trace radioisotope|From decay]]
|- bgcolor="{{element color|s-block}}"
|| 88  || '''Ra''' || [[Radium]] || [[s-block]] || [Rn] 7s<sup>2</sup> || From decay
|- bgcolor="{{element color|f-block}}"
|| 89 || '''Ac''' || [[Actinium]] || [[f-block]] || [Rn] 6d<sup>1</sup> 7s<sup>2</sup> (*) || From decay
|- bgcolor="{{element color|f-block}}"
|| 90 || '''Th''' || [[Thorium]] || [[f-block]] || [Rn] 6d<sup>2</sup> 7s<sup>2</sup> (*) || [[Primordial nuclide|Primordial]]
|- bgcolor="{{element color|f-block}}"
|| 91 || '''Pa''' || [[Protactinium]] || [[f-block]] || [Rn] 5f<sup>2</sup> 6d<sup>1</sup> 7s<sup>2</sup> (*) || From decay
|- bgcolor="{{element color|f-block}}"
|| 92 || '''U''' || [[Uranium]] || [[f-block]] || [Rn] 5f<sup>3</sup> 6d<sup>1</sup> 7s<sup>2</sup> (*) || Primordial
|- bgcolor="{{element color|f-block}}"
|| 93 || '''Np''' || [[Neptunium]] || [[f-block]] || [Rn] 5f<sup>4</sup> 6d<sup>1</sup> 7s<sup>2</sup> (*) || From decay
|- bgcolor="{{element color|f-block}}"
|| 94 || '''Pu''' || [[Plutonium]] || [[f-block]] || [Rn] 5f<sup>6</sup> 7s<sup>2</sup> || From decay
|- bgcolor="{{element color|f-block}}"
|| 95 || '''Am''' || [[Americium]] || [[f-block]] || [Rn] 5f<sup>7</sup> 7s<sup>2</sup> || [[Synthetic element|Synthetic]]
|- bgcolor="{{element color|f-block}}"
|| 96 || '''Cm''' || [[Curium]] || [[f-block]] || [Rn] 5f<sup>7</sup> 6d<sup>1</sup> 7s<sup>2</sup> (*) || Synthetic
|- bgcolor="{{element color|f-block}}"
|| 97 || '''Bk''' || [[Berkelium]] || [[f-block]] || [Rn] 5f<sup>9</sup> 7s<sup>2</sup> || Synthetic
|- bgcolor="{{element color|f-block}}"
|| 98 || '''Cf''' || [[Californium]] || [[f-block]] || [Rn] 5f<sup>10</sup> 7s<sup>2</sup> || Synthetic
|- bgcolor="{{element color|f-block}}"
|| 99 || '''Es''' || [[Einsteinium]] || [[f-block]] || [Rn] 5f<sup>11</sup> 7s<sup>2</sup> || Synthetic
|- bgcolor="{{element color|f-block}}"
|| 100 || '''Fm''' || [[Fermium]] || [[f-block]] || [Rn] 5f<sup>12</sup> 7s<sup>2</sup> || Synthetic
|- bgcolor="{{element color|f-block}}"
|| 101 || '''Md''' || [[Mendelevium]] || [[f-block]]|| [Rn] 5f<sup>13</sup> 7s<sup>2</sup> || Synthetic
|- bgcolor="{{element color|f-block}}"
|| 102 || '''No''' || [[Nobelium]] || [[f-block]] || [Rn] 5f<sup>14</sup> 7s<sup>2</sup>|| Synthetic
|- bgcolor="{{element color|d-block}}"
|| 103  || '''Lr''' || [[Lawrencium]] || [[d-block]] || [Rn] 5f<sup>14</sup> 7s<sup>2</sup> 7p<sup>1</sup> (*) || Synthetic
|- bgcolor="{{element color|d-block}}"
|| 104  || '''Rf''' || [[Rutherfordium]] || [[d-block]] || [Rn] 5f<sup>14</sup> 6d<sup>2</sup> 7s<sup>2</sup> || Synthetic
|- bgcolor="{{element color|d-block}}"
|| 105  || '''Db''' || [[Dubnium]] || [[d-block]] || [Rn] 5f<sup>14</sup> 6d<sup>3</sup> 7s<sup>2</sup> || Synthetic
|- bgcolor="{{element color|d-block}}"
|| 106  || '''Sg''' || [[Seaborgium]] || [[d-block]] || [Rn] 5f<sup>14</sup> 6d<sup>4</sup> 7s<sup>2</sup> || Synthetic
|- bgcolor="{{element color|d-block}}"
|| 107  || '''Bh''' || [[Bohrium]] || [[d-block]] || [Rn] 5f<sup>14</sup> 6d<sup>5</sup> 7s<sup>2</sup> || Synthetic
|- bgcolor="{{element color|d-block}}"
|| 108 || '''Hs''' || [[Hassium]] || [[d-block]] || [Rn] 5f<sup>14</sup> 6d<sup>6</sup> 7s<sup>2</sup> || Synthetic
|- bgcolor="{{element color|d-block}}"
|| 109 || '''Mt''' || [[Meitnerium]] || [[d-block]] || [Rn] 5f<sup>14</sup> 6d<sup>7</sup> 7s<sup>2</sup> (?) || Synthetic
|- bgcolor="{{element color|d-block}}"
|| 110 || '''Ds''' || [[Darmstadtium]] || [[d-block]] || [Rn] 5f<sup>14</sup> 6d<sup>8</sup> 7s<sup>2</sup> (?) || Synthetic
|- bgcolor="{{element color|d-block}}"
|| 111 || '''Rg''' || [[Roentgenium]] || [[d-block]] || [Rn] 5f<sup>14</sup> 6d<sup>9</sup> 7s<sup>2</sup> (?) <!-- YES, IT'S REALLY EXPECTED TO BE DIFFERENT FROM COPPER, SILVER, AND GOLD --> || Synthetic
|- bgcolor="{{element color|d-block}}"
|| 112 || '''Cn''' || [[Copernicium]] || [[d-block]] || [Rn] 5f<sup>14</sup> 6d<sup>10</sup> 7s<sup>2</sup> (?) || Synthetic
|- bgcolor="{{element color|p-block}}"
|| 113 || '''Nh''' || [[Nihonium]] || [[p-block]] || [Rn] 5f<sup>14</sup> 6d<sup>10</sup> 7s<sup>2</sup> 7p<sup>1</sup> (?) || Synthetic
|- bgcolor="{{element color|p-block}}"
|| 114 || '''Fl''' || [[Flerovium]] || [[p-block]] || [Rn] 5f<sup>14</sup> 6d<sup>10</sup> 7s<sup>2</sup> 7p<sup>2</sup> (?) || Synthetic
|- bgcolor="{{element color|p-block}}"
|| 115 || '''Mc''' || [[Moscovium]] || [[p-block]] || [Rn] 5f<sup>14</sup> 6d<sup>10</sup> 7s<sup>2</sup> 7p<sup>3</sup> (?) || Synthetic
|- bgcolor="{{element color|p-block}}"
|| 116 || '''Lv''' || [[Livermorium]] || [[p-block]] || [Rn] 5f<sup>14</sup> 6d<sup>10</sup> 7s<sup>2</sup> 7p<sup>4</sup> (?) || Synthetic
|- bgcolor="{{element color|p-block}}"
|| 117 || '''Ts''' || [[Tennessine]] || [[p-block]] || [Rn] 5f<sup>14</sup> 6d<sup>10</sup> 7s<sup>2</sup> 7p<sup>5</sup> (?) || Synthetic
|- bgcolor="{{element color|p-block}}"
|| 118 || '''Og''' || [[Oganesson]] || [[p-block]] || [Rn] 5f<sup>14</sup> 6d<sup>10</sup> 7s<sup>2</sup> 7p<sup>6</sup> (?) || Synthetic
|}

(?) Prediction

(*) Exception to the [[Madelung rule]].

In many periodic tables, the f-block is erroneously shifted one element to the right, so that lanthanum and actinium become d-block elements, and Ce–Lu and Th–Lr form the f-block tearing the d-block into two very uneven portions. This is a holdover from early erroneous measurements of electron configurations.<ref name="Jensen1982">{{cite journal |title=The Positions of Lanthanum (Actinium) and Lutetium (Lawrencium) in the Periodic Table |author=William B. Jensen |journal=J. Chem. Educ. |year=1982 |volume=59 |issue = 8|pages=634–636 |doi=10.1021/ed059p634|bibcode=1982JChEd..59..634J }}</ref> [[Lev Landau]] and [[Evgeny Lifshitz]] pointed out in 1948 that lutetium is not an f-block element,<ref name=Landau>{{cite book
 |author=[[Lev Landau|L. D. Landau]], [[Evgeny Lifshitz|E. M. Lifshitz]]
 |year=1958
 |title=Quantum Mechanics: Non-Relativistic Theory
 |edition=1st |volume=3
 |publisher=[[Pergamon Press]]
 |pages=256–7
}}</ref> and since then physical, chemical, and electronic evidence has overwhelmingly supported that the f-block contains the elements La–Yb and Ac–No,<ref name=Jensen1982/><ref name=Fluck/> as shown here and as supported by [[International Union of Pure and Applied Chemistry]] reports dating from 1988<ref name="Fluck">{{cite journal |last1=Fluck |first1=E. |year=1988 |title=New Notations in the Periodic Table |journal=[[Pure and Applied Chemistry|Pure Appl. Chem.]] |volume=60 |pages=431–436|doi=10.1351/pac198860030431 |url=https://www.iupac.org/publications/pac/1988/pdf/6003x0431.pdf |access-date=24 March 2012 |issue=3 |s2cid=96704008 |url-status=live |archive-url=https://web.archive.org/web/20120325152951/https://www.iupac.org/publications/pac/1988/pdf/6003x0431.pdf |archive-date=25 March 2012}}</ref> and 2021.<ref name="2021IUPAC">{{cite journal |last1=Scerri |first1=Eric |date=18 January 2021 |title=Provisional Report on Discussions on Group 3 of the Periodic Table |url=https://iupac.org/wp-content/uploads/2021/04/ChemInt_Jan2021_PP.pdf |journal=Chemistry International |volume=43 |issue=1 |pages=31–34 |doi=10.1515/ci-2021-0115 |s2cid=231694898 |access-date=9 April 2021 |archive-date=13 April 2021 |archive-url=https://web.archive.org/web/20210413150110/https://iupac.org/wp-content/uploads/2021/04/ChemInt_Jan2021_PP.pdf |url-status=live }}</ref>

=== S-block ===
{{main|Francium|Radium}}
Francium and radium make up the s-block elements of the 7th period.

'''Francium''' '''(Fr, atomic number 87)''' is a highly [[radioactive]] metal that decays into astatine, [[radium]], or [[radon]]. It is one of the two least [[electronegative]] elements; the other is [[caesium]]<!--, and is the [[Abundance of the chemical elements|second rarest]] naturally occurring element (after [[astatine]])-->. As an [[alkali metal]], it has one [[valence electron]]. Francium was discovered by [[Marguerite Perey]] in [[France]] (from which the element takes its name) in 1939.<ref>{{Cite web |title=Francium {{!}} Radioactive, Alkali Metal, Rare {{!}} Britannica |url=https://www.britannica.com/science/francium |access-date=2023-10-19 |website=www.britannica.com |language=en}}</ref> It was the last element discovered in [[nature]], rather than by synthesis.<ref group="note">Some elements discovered through synthesis, such as [[technetium]], have later been found in nature.</ref> Outside the laboratory, francium is extremely rare, with trace amounts found in [[uranium]] and [[thorium]] ores, where the [[isotope]] francium-223 continually forms and decays. As little as 20–30&nbsp;g (one ounce) exists at any given time throughout [[Earth's crust]]; the other isotopes are entirely synthetic. The largest amount produced in the laboratory was a cluster of more than 300,000 atoms.<ref name=chemnews>{{cite journal|url=http://pubs.acs.org/cen/80th/francium.html|title=Francium|journal=Chemical and Engineering News|year=2003|author=Luis A. Orozco }}</ref>

'''Radium (Ra, atomic number 88)''' is an almost pure-white [[alkaline earth metal]], but it readily [[oxidize]]s, reacting with nitrogen (rather than oxygen) on exposure to air, becoming black in color. All [[isotopes of radium]] are [[radioactive]]; the most stable is [[radium-226]], which has a [[half-life]] of 1601 years and [[Radioactive decay|decays]] into [[radon]]. Due to such instability, radium [[luminescence|luminesces]], glowing a faint blue. Radium, in the form of [[radium chloride]], was [[discovery of the chemical elements|discovered]] by [[Marie Curie|Marie]] and [[Pierre Curie]] in 1898. They extracted the radium compound from [[uraninite]] and published the discovery at the [[French Academy of Sciences]] five days later. Radium was isolated in its [[metal]]lic state by Marie Curie and [[André-Louis Debierne]] through [[electrolysis]] of radium chloride in 1910. Since its discovery, it has given names such as [[radon-222|radium A]] and [[thallium-210|radium C{{sub|2}}]] to several isotopes of other elements that are [[decay product]]s of radium-226. In nature, radium is found in [[uranium]] ores in trace amounts as small as a seventh of a gram per ton of [[uraninite]]. Radium is not necessary for living things, and adverse health effects are likely when it is incorporated into biochemical processes due to its radioactivity and chemical reactivity.

=== Actinides ===
{{main|Actinide}}
[[File:Nagasakibomb.jpg|thumb|The [[Fat Man|atomic bomb]] [[Atomic bombings of Hiroshima and Nagasaki|dropped on Nagasaki]] had a [[plutonium]] charge.<ref>[https://web.archive.org/web/20101122185847/http://www.cfo.doe.gov/me70/manhattan/nagasaki.htm The Manhattan Project. An Interactive History]. US Department of Energy</ref>]]
The '''actinide''' or '''actinoid''' ([[Chemical nomenclature|IUPAC nomenclature]]) series encompasses the 15 [[metal]]lic [[chemical element]]s with [[atomic number]]s from 89 to 103, [[actinium]] through [[lawrencium]].<ref name="Gray" >{{cite book|last=Gray|first=Theodore|title=The Elements: A Visual Exploration of Every Known Atom in the Universe|year=2009|publisher=Black Dog & Leventhal Publishers|location=New York|isbn=978-1-57912-814-2|page=[https://archive.org/details/elementsvisualex0000gray/page/240 240]|url=https://archive.org/details/elementsvisualex0000gray/page/240}}</ref><ref>[https://www.britannica.com/EBchecked/topic/4354/actinoid-element Actinide element], Encyclopædia Britannica on-line</ref><ref>Though "actinoid" (rather than "actinide") means "actinium-like" and therefore should exclude actinium, that element is usually included in the series.</ref><ref>{{cite book|last=Connelly|first=Neil G.|title=Nomenclature of Inorganic Chemistry|publisher=[[Royal Society of Chemistry]]|location=London|year=2005|chapter-url=https://books.google.com/books?id=w1Kf1CakyZIC&pg=PA52|page=52|chapter=Elements|isbn=978-0-85404-438-2|display-authors=etal}}</ref>

The actinide series is named after its first element actinium. All but one of the actinides are [[f-block]] elements, corresponding to the filling of the 5f [[electron shell]]; lawrencium, a [[d-block]] element, is also generally considered an actinide. In comparison with the [[lanthanides]], also mostly [[f-block]] elements, the actinides show much more variable [[valence (chemistry)|valence]].

Of the actinides, [[thorium]] and [[uranium]] occur naturally in substantial, [[Primordial nuclide|primordial]], quantities. Radioactive decay of uranium produces transient amounts of [[actinium]], [[protactinium]] and [[plutonium]], and atoms of [[neptunium]] and [[plutonium]] are occasionally produced from [[Nuclear transmutation|transmutation]] in [[uranium ore]]s. The other actinides are purely [[synthetic elements]], though the first six actinides after plutonium would have been produced at [[Oklo]] (and long since decayed away), and [[curium]] almost certainly previously existed in nature as an [[extinct radionuclide]].<ref name="Gray" /><ref name=g1250>Greenwood, p. 1250</ref>  Nuclear tests have released at least six actinides heavier than plutonium into the [[natural environment|environment]]; analysis of debris from a 1952 [[hydrogen bomb]] explosion showed the presence of [[americium]], [[curium]], [[berkelium]], [[californium]], [[einsteinium]] and [[fermium]].<ref>{{cite journal|last1=Fields|first1=P.|last2=Studier|first2=M.|last3=Diamond|first3=H.|last4=Mech|first4=J.|last5=Inghram|first5=M.|last6=Pyle|first6=G.|last7=Stevens|first7=C.|last8=Fried|first8=S.|last9=Manning|first9=W. |title=Transplutonium Elements in Thermonuclear Test Debris|journal=Physical Review|volume=102|issue=1|page=180|year=1956|doi=10.1103/PhysRev.102.180|bibcode = 1956PhRv..102..180F  }}</ref>

All actinides are [[radioactive]] and release energy upon radioactive decay; naturally occurring uranium and thorium, and synthetically produced plutonium are the most abundant actinides on Earth. These are used in [[nuclear reactor]]s and [[nuclear weapons]]. Uranium and thorium also have diverse current or historical uses, and americium is used in the [[ionization chamber]]s of most modern [[smoke detector]]s.

In presentations of the [[periodic table]], the lanthanides and the actinides are customarily shown as two additional rows below the main body of the table,<ref name="Gray" /> with placeholders or else a selected single element of each series (either [[lanthanum]] or [[lutetium]], and either [[actinium]] or [[lawrencium]], respectively) shown in a single cell of the main table, between [[barium]] and [[hafnium]], and [[radium]] and [[rutherfordium]], respectively.  This convention is entirely a matter of [[aesthetics]] and formatting practicality; a rarely used [[Periodic_table_(detailed_cells)#32-column_layout|wide-formatted periodic table]] (32 columns) shows the lanthanide and actinide series in their proper columns, as parts of the table's sixth and seventh rows (periods).

=== Transactinides ===
{{main|Transactinide elements}}
''Transactinide elements'' (also, '''transactinides''', or '''super-heavy elements''', or '''superheavies''') are the [[chemical element]]s with [[atomic number]]s greater than those of the [[actinide]]s, the heaviest of which is [[lawrencium]] (103).<ref>[http://www.iupac.org/reports/provisional/abstract04/connelly_310804.html IUPAC Provisional Recommendations for the Nomenclature of Inorganic Chemistry (2004)] {{webarchive|url=https://web.archive.org/web/20061027174015/http://www.iupac.org/reports/provisional/abstract04/connelly_310804.html |date=2006-10-27 }} (online draft of an updated version of the "''Red Book''" IR 3–6)</ref><ref>{{cite book |editor1-first=Lester R. |editor1-last=Morss |editor2-first=Norman M. |editor2-last=Edelstein |editor3-first=Jean |editor3-last=Fuger |title=The Chemistry of the Actinide and Transactinide Elements |edition=3rd |year=2006 |publisher=Springer |location=Dordrecht, The Netherlands |isbn=978-1-4020-3555-5}}</ref> All transactinides of period 7 have been discovered, up to [[oganesson]] (element 118).

Superheavies are also [[transuranic element]]s, that is, have atomic number greater than that of [[uranium]] (92). The further distinction of having an atomic number greater than the actinides is significant in several ways:
*The transactinide elements all have electrons in the 6d [[Electron subshell|subshell]] in their ground state (and thus are placed in the [[d-block]]).
*Even the longest-lived known isotopes of many transactinides have extremely short half-lives, measured in seconds or smaller units.
*The [[element naming controversy]] involved the first five or six transactinides. These elements thus used three-letter [[Systematic element name|systematic names]] for many years after their discovery was confirmed. (Usually, the three-letter symbols are replaced with two-letter symbols relatively soon after a discovery has been confirmed.)

Transactinides are [[radioactive]] and have only been obtained synthetically in laboratories. None of these elements has ever been collected in a macroscopic sample. Transactinides are all named after scientists, or important locations involved in the synthesis of the elements.

Chemistry Nobel Prize winner [[Glenn T. Seaborg]], who first proposed the [[actinide concept]] which led to the acceptance of the [[actinide series]], also proposed the existence of a transactinide series ranging from element 104 to 121 and a [[superactinide series]] approximately spanning elements 122 to 153. The transactinide [[seaborgium]] is named in his honor.

IUPAC defines an element to exist if its lifetime is longer than 10{{sup|−14}} second, the time needed to form an electron cloud.<ref>{{Cite web | url=http://www.kernchemie.de/Transactinides/Transactinide-2/transactinide-2.html | title=Kernchemie}}</ref>

==Notes==
{{Reflist|group=note}}

==References==
{{reflist}}

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