Editing Germanium (section)

== History ==
<!--[[File:medeleeff by repin.jpg|thumb|Dmitri Mendeleev|alt=An old man with a gray-white beard sitting by the table, holding an old open book in his laps. He wears a red-blue gown and black square hat. There are two thick old books on the table.]]
[[File:Winkler Clemens.jpg|thumb|[[Clemens Winkler]]|alt=Photo of a bust of a middle-aged man in a suit with a white short beard and gray moustache.]] THESE PHOTOS are hard to arrange due to the infobox; they are not essential for Germanium-->
[[File:Mendeleev 1869 prediction of germanium (detail).svg|upright|left|thumb |Prediction of germanium, "?=70" (periodic table 1869)]]
In his report on ''The Periodic Law of the Chemical Elements'' in 1869, the Russian chemist [[Dmitri Mendeleev]] predicted the existence of several unknown chemical elements, including one that would fill a gap in the [[group 14 element|carbon family]], located between [[silicon]] and [[tin]].<ref>{{cite journal |first=Masanori |last=Kaji |title=D. I. Mendeleev's concept of chemical elements and ''The Principles of Chemistry'' |journal=Bulletin for the History of Chemistry |volume=27 |issue=1 |pages=4–16 |year=2002 |doi=10.70359/bhc2002v027p004 |url=http://www.scs.uiuc.edu/~mainzv/HIST/awards/OPA%20Papers/2005-Kaji.pdf |access-date=2008-08-20 |archive-url=https://web.archive.org/web/20081217080509/http://www.scs.uiuc.edu/~mainzv/HIST/awards/OPA%20Papers/2005-Kaji.pdf |archive-date=2008-12-17 |url-status=dead}}</ref> Because of its position in his periodic table, Mendeleev called it ''ekasilicon (Es)'', and he estimated its [[atomic weight]] to be 70 (later 72).<!-- Mendeleev studied several minerals in an unsuccessful search for this new element.<ref name="vdk">{{cite web |title=Elementymology & Elements Multidict: Germanium |first=Peter |last=van der Krogt |url=http://elements.vanderkrogt.net/element.php?sym=Ge |access-date=2008-08-20}}</ref> -->

<!-- [[File:Winkler preparate 1886 1904.png|thumb|left|Samples of germanium compounds prepared by Freiberg University's [[Clemens Winkler]], discoverer of the element]] -->In mid-1885, at a mine near [[Freiberg, Saxony]], a new [[mineral]] was discovered and named ''[[argyrodite]]'' because of its high [[silver]] content.{{NoteTag|From Greek, ''argyrodite'' means ''silver-containing''.<ref>{{cite report |url=http://www.handbookofmineralogy.org/pdfs/argyrodite.pdf |publisher=Mineral Data Publishing |title=Argyrodite – {{chem|Ag|8|GeS|6}} |access-date=2008-09-01 |date= |archive-date=2016-03-03 |archive-url=https://web.archive.org/web/20160303221645/http://www.handbookofmineralogy.org/pdfs/argyrodite.pdf |url-status=live}}</ref>}} The chemist [[Clemens Winkler]] analyzed this new mineral, which proved to be a combination of silver, sulfur, and a new element. Winkler was able to isolate the new element in 1886 and found it similar to [[antimony]]. He initially considered the new element to be eka-antimony, but was soon convinced that it was instead eka-silicon.<ref name="Winkle2" /><ref name="isolation">{{cite journal |journal=Berichte der Deutschen Chemischen Gesellschaft |volume=19 |issue=1 |pages=210–211 |title=Germanium, Ge, a New Nonmetal Element |language=de |first=Clemens |last=Winkler |author-link=Clemens Winkler |year=1887 |doi=10.1002/cber.18860190156 |url=http://gallica.bnf.fr/ark%3A/12148/bpt6k90705g/f212.chemindefer |url-status=dead |archive-url=https://web.archive.org/web/20081207033757/http://dbhs.wvusd.k12.ca.us/webdocs/Chem-History/Disc-of-Germanium.html |archive-date=December 7, 2008}}</ref> Before Winkler published his results on the new element, he decided that he would name his element ''neptunium'', since the recent discovery of planet [[Neptune]] in 1846 had similarly been preceded by mathematical predictions of its existence.{{NoteTag|Just as the existence of the new element had been predicted, the existence of the planet [[Neptune]] had been predicted in about 1843 by the two mathematicians [[John Couch Adams]] and [[Urbain Le Verrier]], using the calculation methods of [[celestial mechanics]]. They did this in attempts to explain the fact that the planet [[Uranus]], upon very close observation, appeared to be being pulled slightly out of position in the sky.<ref>{{cite journal |first=J. C. |last=Adams |bibcode=1846MNRAS...7..149A |title=Explanation of the observed irregularities in the motion of Uranus, on the hypothesis of disturbance by a more distant planet |journal=[[Monthly Notices of the Royal Astronomical Society]] |volume=7 |issue=9 |pages=149–152 |date=November 13, 1846 |doi=10.1093/mnras/7.9.149 |url=https://zenodo.org/record/1431905 |access-date=August 25, 2019 |archive-date=May 2, 2019 |archive-url=https://web.archive.org/web/20190502014753/https://zenodo.org/record/1431905/files/article.pdf |url-status=live |doi-access=free}}</ref> [[James Challis]] started searching for it in July 1846, and he sighted this planet on September 23, 1846.<ref>{{cite journal |first=Rev. J. |last=Challis |bibcode=1846MNRAS...7..145C |title=Account of observations at the Cambridge observatory for detecting the planet exterior to Uranus |journal=Monthly Notices of the Royal Astronomical Society |volume=7 |issue=9 |pages=145–149 |date=November 13, 1846 |doi=10.1093/mnras/7.9.145 |url=https://zenodo.org/record/1431903 |access-date=August 25, 2019 |archive-date=May 4, 2019 |archive-url=https://web.archive.org/web/20190504065619/https://zenodo.org/record/1431903/files/article.pdf |url-status=live |doi-access=free}}</ref>}} However, the name "neptunium" had already been given to another proposed chemical element (though not the element that today bears the name [[neptunium]], which was discovered in 1940).{{NoteTag|R. Hermann published claims in 1877 of his discovery of a new element beneath [[tantalum]] in the periodic table, which he named ''neptunium'', after the Greek god of the oceans and seas.<ref>{{cite journal |title=Scientific Miscellany |journal=The Galaxy |volume=24 |issue=1 |date=July 1877 |page=131 |isbn=978-0-665-50166-1 |first=Robert |last=Sears |oclc=16890343}}</ref><ref>{{cite journal |title=Editor's Scientific Record |journal=Harper's New Monthly Magazine |volume=55 |issue=325 |date=June 1877 |pages=152–153 |url=http://cdl.library.cornell.edu/cgi-bin/moa/moa-cgi?notisid=ABK4014-0055-21 |access-date=2008-09-22 |archive-date=2012-05-26 |archive-url=https://archive.today/20120526215615/http://cdl.library.cornell.edu/cgi-bin/moa/moa-cgi?notisid=ABK4014-0055-21 |url-status=live}}</ref> However this [[metal]] was later recognized to be an [[alloy]] of the elements [[niobium]] and tantalum.<ref>{{cite web |title=Elementymology & Elements Multidict: Niobium |first=Peter |last=van der Krogt |url=http://elements.vanderkrogt.net/element.php?sym=Nb |access-date=2008-08-20 |archive-date=2010-01-23 |archive-url=https://web.archive.org/web/20100123002753/http://elements.vanderkrogt.net/element.php?sym=Nb |url-status=live}}</ref> The name "[[neptunium]]" was later given to the synthetic element one step past [[uranium]] in the Periodic Table, which was discovered by [[nuclear physics]] researchers in 1940.<ref>{{cite book |title=Nobel Lectures, Chemistry 1942–1962 |publisher=Elsevier |date=1964 |chapter=The Nobel Prize in Chemistry 1951: presentation speech |first=A. |last=Westgren |chapter-url=http://nobelprize.org/nobel_prizes/chemistry/laureates/1951/press.html |access-date=2008-09-18 |archive-date=2008-12-10 |archive-url=https://web.archive.org/web/20081210174205/http://nobelprize.org/nobel_prizes/chemistry/laureates/1951/press.html |url-status=live}}</ref>}} So instead, Winkler named the new element ''germanium'' (from the [[Latin]] word, ''[[Germania]]'', for Germany) in honor of his homeland.<ref name="isolation" /> Argyrodite proved empirically to be Ag<sub>8</sub>GeS<sub>6</sub>.
Because this new element showed some similarities with the elements [[arsenic]] and antimony, its proper place in the periodic table was under consideration, but its similarities with Dmitri Mendeleev's predicted element "ekasilicon" confirmed that place on the periodic table.<ref name="isolation" /><ref>{{cite journal |journal=The Manufacturer and Builder |url=http://cdl.library.cornell.edu/cgi-bin/moa/pageviewer?frames=1&coll=moa&view=50&root=%2Fmoa%2Fmanu%2Fmanu0018%2F&tif=00187.TIF |year=1887 |title=Germanium, a New Non-Metallic Element |page=181 |access-date=2008-08-20 |archive-date=2008-12-19 |archive-url=https://web.archive.org/web/20081219162737/http://cdl.library.cornell.edu/cgi-bin/moa/pageviewer?frames=1&coll=moa&view=50&root=%2Fmoa%2Fmanu%2Fmanu0018%2F&tif=00187.TIF |url-status=live}}</ref> With further material from 500&nbsp;kg of ore from the mines in Saxony, Winkler confirmed the chemical properties of the new element in 1887.<ref name="Winkle2">{{cite journal |first=Clemens |last=Winkler |author-link=Clemens Winkler |journal=J. Prak. Chemie |volume=36 |issue=1 |date=1887 |pages=177–209 |title=Mittheilungen über des Germanium. Zweite Abhandlung |doi=10.1002/prac.18870360119 |url=http://gallica.bnf.fr/ark:/12148/bpt6k90799n/f183.table |access-date=2008-08-20 |language=de |archive-date=2012-11-03 |archive-url=https://web.archive.org/web/20121103012004/http://gallica.bnf.fr/ark:/12148/bpt6k90799n/f183.table |url-status=live}}</ref><ref name="isolation" /><ref>{{cite journal |first=O. |last=Brunck |title=Obituary: Clemens Winkler |journal=Berichte der Deutschen Chemischen Gesellschaft |volume=39 |issue=4 |year=1886 |pages=4491–4548 |doi=10.1002/cber.190603904164 |url=https://zenodo.org/record/1426200 |language=de |access-date=2020-06-07 |archive-date=2020-08-01 |archive-url=https://web.archive.org/web/20200801004057/https://zenodo.org/record/1426200 |url-status=live}}</ref> He also determined an atomic weight of 72.32 by analyzing pure [[germanium tetrachloride]] ({{chem|GeCl|4}}), while [[Lecoq de Boisbaudran]] deduced 72.3 by a comparison of the lines in the spark [[spectrum]] of the element.<ref>{{cite journal |title=Sur le poids atomique du germanium |first=M. Lecoq |last=de Boisbaudran |journal=Comptes Rendus |year=1886 |volume=103 |page=452 |url=http://gallica.bnf.fr/ark:/12148/bpt6k3059r/f454.table |access-date=2008-08-20 |language=fr |archive-date=2013-06-20 |archive-url=https://web.archive.org/web/20130620032945/http://gallica.bnf.fr/ark:/12148/bpt6k3059r/f454.table |url-status=live}}</ref>

Winkler was able to prepare several new compounds of germanium, including [[Germanium fluoride|fluorides]], [[Germanium chloride|chlorides]], [[Germanium sulfide (disambiguation)|sulfides]]<!--intentional link to DAB page-->, [[Germanium dioxide|dioxide]], and [[tetraethylgermane]] (Ge(C<sub>2</sub>H<sub>5</sub>)<sub>4</sub>), the first organogermane.<ref name="Winkle2" /> The physical data from those compounds—which corresponded well with Mendeleev's predictions—made the discovery an important confirmation of Mendeleev's idea of element [[Periodic table|periodicity]]. Here is a comparison between the prediction and Winkler's data:<ref name="Winkle2" />

<div style="float: center; margin: 5px;">
{| class="wikitable"
|-
! Property !! Ekasilicon<br />{{nobold|Mendeleev<br />prediction (1871)}} !! Germanium<br />{{nobold|Winkler<br />discovery (1887)}}
|-
| atomic mass || 72.64 || 72.63
|-
| density (g/cm<sup>3</sup>) || 5.5 || 5.35
|-
| melting point (°C) || high || 947
|-
| color || gray || gray
|-
| oxide type || [[refractory]] dioxide || refractory dioxide
|-
| oxide density (g/cm<sup>3</sup>) || 4.7 || 4.7
|-
| oxide activity || feebly basic || feebly basic
|-
| chloride boiling point (°C) || under 100 || 86 (GeCl<sub>4</sub>)
|-
| chloride density (g/cm<sup>3</sup>) || 1.9 || 1.9
|}</div>

Until the late 1930s, germanium was thought to be a poorly conducting [[metal]].<ref name="DOE">{{cite journal |title=Germanium: From Its Discovery to SiGe Devices |author=Haller, E. E. |website=Department of Materials Science and Engineering, University of California, Berkeley, and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley |url=http://www.osti.gov/bridge/servlets/purl/922705-bthJo6/922705.PDF |access-date=2008-08-22 |date=2006-06-14 |archive-date=2019-07-10 |archive-url=https://web.archive.org/web/20190710154435/http://www.osti.gov/bridge/servlets/purl/922705-bthJo6/922705.PDF |url-status=live}}</ref> Germanium did not become economically significant until after 1945 when its properties as an [[electronics|electronic]] semiconductor were recognized. During [[World War II]], small amounts of germanium were used in some special [[electronics|electronic devices]], mostly [[diode]]s.<ref>{{cite news |author=W. K. |url=http://select.nytimes.com/gst/abstract.html?res=F30715FE3F5B157A93C2A8178ED85F478585F9 |newspaper=The New York Times |title=Germanium for Electronic Devices |access-date=2008-08-22 |date=1953-05-10 |archive-date=2013-06-13 |archive-url=https://web.archive.org/web/20130613202934/http://select.nytimes.com/gst/abstract.html?res=F30715FE3F5B157A93C2A8178ED85F478585F9 |url-status=live}}</ref><ref>{{cite web |url=http://www.computerhistory.org/semiconductor/timeline/1941-semiconductor.html |title=1941 – Semiconductor diode rectifiers serve in WW II |publisher=Computer History Museum |access-date=2008-08-22 |archive-date=2008-09-24 |archive-url=https://web.archive.org/web/20080924135754/http://www.computerhistory.org/semiconductor/timeline/1941-semiconductor.html |url-status=live}}</ref> The first major use was the point-contact [[Schottky diode]]s for [[radar]] pulse detection during the War.<ref name="DOE" /> The first [[silicon–germanium]] alloys were obtained in 1955.<ref>{{cite web |url=http://www.sp.phy.cam.ac.uk/~SiGe/Silicon%20Germanium%20(SiGe)%20History.html |title=SiGe History |publisher=University of Cambridge |access-date=2008-08-22 |url-status=dead |archive-url=https://web.archive.org/web/20080805204801/http://www.sp.phy.cam.ac.uk/~SiGe/Silicon%20Germanium%20%28SiGe%29%20History.html |archive-date=2008-08-05}}</ref> Before 1945, only a few hundred kilograms of germanium were produced in smelters each year, but by the end of the 1950s, the annual worldwide production had reached {{convert|40|MT|ST|lk=on|abbr=off}}.<ref name="acs">{{cite news |url=http://pubs.acs.org/cen/80th/print/germanium.html |year=2003 |title=Germanium |first=Bethany |last=Halford |work=Chemical & Engineering News |publisher=American Chemical Society |access-date=2008-08-22 |archive-date=2008-05-13 |archive-url=https://web.archive.org/web/20080513180858/http://pubs.acs.org/cen/80th/print/germanium.html |url-status=live}}</ref>

The development of the germanium [[transistor]] in 1948<ref>{{cite journal |journal=Physical Review |volume=74 |issue=2 |pages=230–231 |title=The Transistor, A Semi-Conductor Triode |first=J. |last=Bardeen |author2=Brattain, W. H. |year=1948 |doi=10.1103/PhysRev.74.230 |bibcode=1948PhRv...74..230B |doi-access=free}}</ref> opened the door to countless applications of [[solid state (electronics)|solid state electronics]].<ref>{{cite web |title=Electronics History 4 – Transistors |url=http://www.greatachievements.org/?id=3967 |publisher=National Academy of Engineering |access-date=2008-08-22 |archive-date=2007-10-20 |archive-url=https://web.archive.org/web/20071020030644/http://www.greatachievements.org/?id=3967 |url-status=live}}</ref> From 1950 through the early 1970s, this area provided an increasing market for germanium, but then high-purity silicon began replacing germanium in transistors, diodes, and [[rectifier]]s.<ref name="usgs">{{cite journal |title=Germanium – Statistics and Information |author=U.S. Geological Survey |year=2008 |journal=U.S. Geological Survey, Mineral Commodity Summaries |url=http://minerals.usgs.gov/minerals/pubs/commodity/germanium/ |quote=Select 2008 |access-date=2008-08-28 |archive-date=2008-09-16 |archive-url=https://web.archive.org/web/20080916115005/http://minerals.usgs.gov/minerals/pubs/commodity/germanium/ |url-status=live}}</ref> For example, the company that became [[Fairchild Semiconductor]] was founded in 1957 with the express purpose of producing silicon transistors. Silicon has superior electrical properties, but it requires much greater purity that could not be commercially achieved in the early years of [[solid-state electronics|semiconductor electronics]].<ref>{{cite journal |journal=IEEE Transactions on Electron Devices |volume=ED-23 |issue=7 |date=July 1976 |title=Single Crystals of Germanium and Silicon-Basic to the Transistor and Integrated Circuit |first=Gordon K. |last=Teal |pages=621–639 |doi=10.1109/T-ED.1976.18464 |bibcode=1976ITED...23..621T |s2cid=11910543}}</ref>

Meanwhile, the demand for germanium for [[fiber optics|fiber optic]] communication networks, infrared [[night vision]] systems, and [[polymerization]] [[catalysts]] increased dramatically.<ref name="acs" /> These end uses represented 85% of worldwide germanium consumption in 2000.<ref name="usgs" /> The US government even designated germanium as a strategic and critical material, calling for a 146&nbsp;[[Short ton|ton]] (132&nbsp;[[tonne]]) supply in the national defense stockpile in 1987.<ref name="acs" />

Germanium differs from silicon in that the supply is limited by the availability of exploitable sources, while the supply of silicon is limited only by production capacity since silicon comes from ordinary sand and [[quartz]]. While silicon could be bought in 1998 for less than $10 per kg,<ref name="acs" /> the price of germanium was almost $800 per kg.<ref name="acs" />