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35-403: Neil Bartlett may refer to: Neil Bartlett (chemist) (1932–2008), chemist who synthesized the first noble-gas compounds Neil Bartlett (playwright) (born 1958), award-winning British director, performer, translator, and writer See also [ edit ] Neal Bartlett (born 1975), English footballer [REDACTED] Topics referred to by

70-981: A diamond anvil cell . Solid argon-hydrogen clathrate ( Ar(H 2 ) 2 ) has the same crystal structure as the MgZn 2 Laves phase . It forms at pressures between 4.3 and 220 GPa, though Raman measurements suggest that the H 2 molecules in Ar(H 2 ) 2 dissociate above 175 GPa. A similar Kr(H 2 ) 4 solid forms at pressures above 5 GPa. It has a face-centered cubic structure where krypton octahedra are surrounded by randomly oriented hydrogen molecules. Meanwhile, in solid Xe(H 2 ) 8 xenon atoms form dimers inside solid hydrogen . Coordination compounds such as Ar·BF 3 have been postulated to exist at low temperatures, but have never been confirmed. Also, compounds such as WHe 2 and HgHe 2 were reported to have been formed by electron bombardment, but recent research has shown that these are probably

105-654: A local supply store. He went on to attend King's College, University of Durham (which went on to become Newcastle University ) in the United Kingdom where he obtained a Bachelor of Science (1954) and then a doctorate (1958) in the inorganic chemistry research group of Dr. P.L. Robinson. In 1958, Bartlett's career began upon being appointed a lecturer in chemistry at the University of British Columbia in Vancouver, BC, Canada where he would ultimately reach

140-479: A mistaken identification. Krypton compounds with other than Kr–F bonds (compounds with atoms other than fluorine ) have also been described. KrF 2 reacts with B(OTeF 5 ) 3 to produce the unstable compound, Kr(OTeF 5 ) 2 , with a krypton- oxygen bond. A krypton- nitrogen bond is found in the cation [H−C≡N−Kr−F] , produced by the reaction of KrF 2 with [H−C≡N−H] [AsF 6 ] below −50 °C. The discovery of HArF

175-416: A noble gas matrix at temperatures of 40 K (−233 °C; −388 °F) or lower, in supersonic jets of noble gas, or under extremely high pressures with metals. The heavier noble gases have more electron shells than the lighter ones. Hence, the outermost electrons are subject to a shielding effect from the inner electrons that makes them more easily ionized , since they are less strongly attracted to

210-474: A part of the function of excimer lasers . Krypton gas reacts with fluorine gas under extreme forcing conditions, forming KrF 2 according to the following equation: KrF 2 reacts with strong Lewis acids to form salts of the [KrF] and [Kr 2 F 3 ] cations . The preparation of KrF 4 reported by Grosse in 1963, using the Claasen method, was subsequently shown to be

245-542: A professor of chemistry until his retirement in 1993. He was also a staff scientist at Lawrence Berkeley National Laboratory from 1969 to 1999. In 2000, he became a naturalized citizen of the United States. He died on 5 August 2008 of a ruptured aortic aneurysm . He lived with his wife Christina Bartlett until his death. They had four children. Bartlett's main specialty was the chemistry of fluorine and of compounds containing fluorine. In 1962, Bartlett prepared

280-399: Is different from Wikidata All article disambiguation pages All disambiguation pages Neil Bartlett (chemist) Neil Bartlett (15 September 1932 – 5 August 2008) was a British chemist who specialized in fluorine and compounds containing fluorine, and became famous for creating the first noble gas compounds . He taught chemistry at the University of British Columbia and

315-744: Is expected to be even more reactive than radon, more like a normal element than a noble gas in its chemistry. Prior to 1962, the only isolated compounds of noble gases were clathrates (including clathrate hydrates ); other compounds such as coordination compounds were observed only by spectroscopic means. Clathrates (also known as cage compounds) are compounds of noble gases in which they are trapped within cavities of crystal lattices of certain organic and inorganic substances. Ar, Kr, Xe and Ne can form clathrates with crystalline hydroquinone . Kr and Xe can appear as guests in crystals of melanophlogite . Helium-nitrogen ( He(N 2 ) 11 ) crystals have been grown at room temperature at pressures ca. 10 GPa in

350-423: Is nearly equal to the ionisation energy of Xe to Xe (1170 kJ mol ), he tried the reaction of Xe with PtF 6 . This yielded a crystalline product, xenon hexafluoroplatinate , whose formula was proposed to be Xe [PtF 6 ] . It was later shown that the compound is actually more complex, containing both [XeF] [PtF 5 ] and [XeF] [Pt 2 F 11 ] . Nonetheless, this

385-414: Is not chemically inert, but its short half-life (3.8 days for Rn) and the high energy of its radioactivity make it difficult to investigate its only fluoride ( RnF 2 ), its reported oxide ( RnO 3 ), and their reaction products. All known oganesson isotopes have even shorter half-lives in the millisecond range and no compounds are known yet, although some have been predicted theoretically. It

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420-486: Is simply liberated as a gas—and so is rivalled only by ozone in this regard. The perxenates are even more powerful oxidizing agents. Xenon-based oxidants have also been used for synthesizing carbocations stable at room temperature, in SO 2 ClF solution. Stable salts of xenon containing very high proportions of fluorine by weight (such as tetrafluoroammonium heptafluoroxenate(VI), [NF 4 ][XeF 7 ] , and

455-432: Is some empirical and theoretical evidence for a few metastable helium compounds which may exist at very low temperatures or extreme pressures. The stable cation [HeH] was reported in 1925, but was not considered a true compound since it is not neutral and cannot be isolated. In 2016 scientists created the helium compound disodium helide ( Na 2 He ) which was the first helium compound discovered. Radon

490-748: The American Chemical Society and the Canadian Society for Chemistry (CSC) as an International Historic Chemical Landmark at the University of British Columbia in recognition of its significance, "fundamental to the scientific understanding of the chemical bond." Bartlett was nominated for a Nobel Prize in Chemistry every year between 1963 and 1966 but did not get the Prize. In January 1963, Bartlett and his graduate student, P. R. Rao, were hospitalized after an explosion in

525-551: The University of California, Berkeley . Neil Bartlett was born on 15 September 1932 in Newcastle-upon-Tyne , England. Bartlett's interest in chemistry dated back to an experiment at Heaton Grammar School when he was only eleven years old, in which he prepared "beautiful, well-formed" crystals by reaction of aqueous ammonia with copper sulfate . He explored chemistry by constructing a makeshift lab in his parents' home using chemicals and glassware he purchased from

560-492: The first noble gas compound , xenon hexafluoroplatinate , Xe [PtF 6 ] . This contradicted established models of the nature of valency , as it was believed that all noble gases were entirely inert to chemical combination. His discovery incited other chemists to discover several other fluorides of xenon: XeF 2 , XeF 4 , and XeF 6 . In 1968 he was awarded the Elliott Cresson Medal . In 1973, he

595-411: The function of excimer lasers . Recently, xenon has been shown to produce a wide variety of compounds of the type XeO n X 2 where n is 1, 2 or 3 and X is any electronegative group, such as CF 3 , C(SO 2 CF 3 ) 3 , N(SO 2 F) 2 , N(SO 2 CF 3 ) 2 , OTeF 5 , O(IO 2 F 2 ) , etc.; the range of compounds is impressive, similar to that seen with

630-579: The heavier noble gases would be able to form compounds with fluorine and oxygen . Specifically, he predicted the existence of krypton hexafluoride ( Kr F 6 ) and xenon hexafluoride ( Xe F 6 ), speculated that XeF 8 might exist as an unstable compound, and suggested that xenic acid would form perxenate salts. These predictions proved quite accurate, although subsequent predictions for XeF 8 indicated that it would be not only thermodynamically unstable, but kinetically unstable . As of 2022, XeF 8 has not been made, although

665-465: The laboratory. As they looked at what they thought might be the first crystals of XeF 2 , the compound exploded, getting shards of glass in the eyes of both men. According to Bartlett, he thought that the compound may have contained water molecules, and he and Rao took off their glasses to get a better look. They were both taken to the hospital for four weeks, and Bartlett was left with damaged vision in one eye. The last piece of glass from this accident

700-431: The neighbouring element iodine , running into the thousands and involving bonds between xenon and oxygen, nitrogen, carbon, boron and even gold, as well as perxenic acid , several halides, and complex ions. The compound [Xe 2 ] [Sb 4 F 21 ] contains a Xe–Xe bond, which is the longest element-element bond known (308.71 pm = 3.0871 Å ). Short-lived excimers of Xe 2 are reported to exist as

735-502: The octafluoroxenate(VI) anion ( [XeF 8 ] ) has been observed. By 1960, no compound with a covalently bound noble gas atom had yet been synthesized. The first published report, in June 1962, of a noble gas compound was by Neil Bartlett , who noticed that the highly oxidising compound platinum hexafluoride ionised O 2 to O + 2 . As the ionisation energy of O 2 to O + 2 (1165 kJ mol )

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770-431: The positively-charged nucleus . This results in an ionization energy low enough to form stable compounds with the most electronegative elements , fluorine and oxygen , and even with less electronegative elements such as nitrogen and carbon under certain circumstances. When the family of noble gases was first identified at the end of the nineteenth century, none of them were observed to form any compounds and so it

805-408: The rank of full professor. During his time at the university he made his discovery that noble gases were indeed reactive enough to form bonds. He remained there until 1966, when he moved to Princeton University as a professor of chemistry and a member of the research staff at Bell Laboratories . He then went on to join the chemistry department at the University of California, Berkeley in 1969 as

840-518: The related tetrafluoroammonium octafluoroxenate(VI) [NF 4 ] 2 [XeF 8 ] ), have been developed as highly energetic oxidisers for use as propellants in rocketry. Xenon fluorides are good fluorinating agents. Clathrates have been used for separation of He and Ne from Ar, Kr, and Xe, and also for the transportation of Ar, Kr, and Xe. (For instance, radioactive isotopes of krypton and xenon are difficult to store and dispose, and compounds of these elements may be more easily handled than

875-427: The result of He being adsorbed on the surface of the metal; therefore, these compounds cannot truly be considered chemical compounds. Hydrates are formed by compressing noble gases in water, where it is believed that the water molecule, a strong dipole, induces a weak dipole in the noble gas atoms, resulting in dipole-dipole interaction. Heavier atoms are more influenced than smaller ones, hence Xe·5.75H 2 O

910-407: The same term This disambiguation page lists articles about people with the same name. If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Neil_Bartlett&oldid=1051619998 " Category : Human name disambiguation pages Hidden categories: Short description

945-702: Was announced in 2000. The compound can exist in low temperature argon matrices for experimental studies, and it has also been studied computationally . Argon hydride ion [ArH] was obtained in the 1970s. This molecular ion has also been identified in the Crab nebula , based on the frequency of its light emissions. There is a possibility that a solid salt of [ArF] could be prepared with [SbF 6 ] or [AuF 6 ] anions. The ions, Ne , [NeAr] , [NeH] , and [HeNe] are known from optical and mass spectrometric studies. Neon also forms an unstable hydrate. There

980-526: Was awarded the prestigious Davy Medal in 2002 for his discovery that the noble gases were not that noble after all. Previous recipients of the Davy Medal had included people as diverse as Robert Wilhelm Bunsen , the inventor of the Bunsen burner , and Albert Ladenburg , who suggested the existence of the compound prismane . In 2006, his research into the reactivity of noble gases was designated jointly by

1015-476: Was doped with a helium atom; with higher pressures (3000 bar), it is possible to achieve a yield of up to 0.1%. Endohedral complexes with argon , krypton and xenon have also been obtained, as well as numerous adducts of He@C 60 . Most applications of noble gas compounds are either as oxidising agents or as a means to store noble gases in a dense form. Xenic acid is a valuable oxidising agent because it has no potential for introducing impurities—xenon

1050-606: Was initially believed that they were all inert gases (as they were then known) which could not form compounds. With the development of atomic theory in the early twentieth century, their inertness was ascribed to a full valence shell of electrons which render them very chemically stable and nonreactive. All noble gases have full s and p outer electron shells (except helium , which has no p sublevel), and so do not form chemical compounds easily. Their high ionization energy and almost zero electron affinity explain their non-reactivity. In 1933, Linus Pauling predicted that

1085-675: Was made a Fellow of the Royal Society (United Kingdom). In 1976 he received the Welch Award in Chemistry for his synthesis of chemical compounds of noble gases and the consequent opening of broad new fields of research in the inorganic chemistry. He was elected a Fellow of the American Academy of Arts and Sciences in 1977. In 1979, he was honored as a Foreign Associate of the National Academy of Sciences . He

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1120-660: Was removed 27 years later. Noble gas compound From the standpoint of chemistry, the noble gases may be divided into two groups: the relatively reactive krypton ( ionisation energy 14.0  eV ), xenon (12.1 eV), and radon (10.7 eV) on one side, and the very unreactive argon (15.8 eV), neon (21.6 eV), and helium (24.6 eV) on the other. Consistent with this classification, Kr, Xe, and Rn form compounds that can be isolated in bulk at or near standard temperature and pressure , whereas He, Ne, Ar have been observed to form true chemical bonds using spectroscopic techniques, but only when frozen into

1155-1102: Was reported in 1963. In this section, the non-radioactive noble gases are considered in decreasing order of atomic weight , which generally reflects the priority of their discovery, and the breadth of available information for these compounds. The radioactive elements radon and oganesson are harder to study and are considered at the end of the section. After the initial 1962 studies on XeF 4 and XeF 2 , xenon compounds that have been synthesized include other fluorides ( XeF 6 ), oxyfluorides ( XeOF 2 , XeOF 4 , XeO 2 F 2 , XeO 3 F 2 , XeO 2 F 4 ) and oxides ( XeO 2 , XeO 3 and XeO 4 ). Xenon fluorides react with several other fluorides to form fluoroxenates, such as sodium octafluoroxenate(VI) ( (Na ) 2 [XeF 8 ] ), and fluoroxenonium salts, such as trifluoroxenonium hexafluoroantimonate ( [XeF 3 ] [SbF 6 ] ). In terms of other halide reactivity, short-lived excimers of noble gas halides such as XeCl 2 or XeCl are prepared in situ, and are used in

1190-529: Was reported to have been the most stable hydrate; it has a melting point of 24 °C. The deuterated version of this hydrate has also been produced. Noble gases can also form endohedral fullerene compounds where the noble gas atom is trapped inside a fullerene molecule. In 1993, it was discovered that when C 60 is exposed to a pressure of around 3 bar of He or Ne, the complexes He@C 60 and Ne@C 60 are formed. Under these conditions, only about one out of every 650,000 C 60 cages

1225-473: Was the first real compound of any noble gas. The first binary noble gas compounds were reported later in 1962. Bartlett synthesized xenon tetrafluoride ( XeF 4 ) by subjecting a mixture of xenon and fluorine to high temperature. Rudolf Hoppe , among other groups, synthesized xenon difluoride ( XeF 2 ) by the reaction of the elements. Following the first successful synthesis of xenon compounds, synthesis of krypton difluoride ( KrF 2 )

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