Erbium discovery

Dysprosium - the atomic number is 66 and the chemical symbol is Dy. The name derives from the Greek dysprositos for hard to get at , due to the difficulty in separating this rare earth element from a holmium mineral in which it was found. Discovery was first claimed by the Swiss chemist Marc Delafontaine in the mineral samarskite in 1878 and he called it philippia. Philippia was subsequently found to be a mixture of terbium and erbium. Dysprosium was later discovered in a holmium sample by the French chemist Paul-Emile Lecoq de Boisbaudron in 1886, who was then credited with the discovery. It was first isolated by the French chemist George Urbain in 1906. 

In the 1800s chemists searched for new elements by fractionating the oxides of rare-earths. Carl Gustaf Mosander s experiments indicated that pure ceria ores were actually contaminated with oxides of lanthanum, a new element. Mosander also fractionated the oxides of yttria into two new elements, erbium and terbium. In 1878 J. Louis Soret (1827—1890) and Marc Delafontaine (1837-1911), through spectroscopic analysis, found evidence of the element holmium, but it was contaminated by the rare-earth dysprosia. Since they could not isolate it and were unable to separate holmium as a pure rare-earth, they did not receive credit for its discovery. 

Cleve s fame rests chiefly, however, on his discoveries among the rare earths. After obtaining some erbia from which all the ytterbia and scandia had been removed, and after noticing that the atomic weight of the erbium was not constant, he succeeded in resolving the earth into three constituents erbia, holmia, and thulia (21). The absorption bands of holmium had already been noticed by the Swiss chemists M. Delafontaine... 

Spectrum of the Glowing Oxide.—Neodymium oxide is one of the very few solids with a discontinuous spectrum. The spectrum which was known long before neodymium was separated from its fellow element praesodymium, was briefly described by Bunsen1 in 1864, who in the same communication mentions the discovery by Bahr2 of the similarly banded spectrum of erbium oxide. Thus far, however, no thorough-going study seems to have been made of this class of spectrum. 

In 1878, French chemist Jean-Charles-Galissard de Marignac reported his analysis of the mineral erbia. Erbia was one of the minerals found a century earlier in an interesting new rock called yttria. The rock had been discovered outside the town of Ytterby, Sweden, in 1787 by Swedish army officer Carl Axel Arrhenius (1757—1824). In the century that followed Arrhenius discovery, chemists worked hard to find out what elements were in yttria. Earlier chemists thought erbia was a new element, but Marignac disagreed. He said that erbia consisted of two new elements, which he called erbium and ytterbium. 

Yttrium is one of four elements named for the same small town of Ytterby, Sweden. The other three elements are erbium, terbium, and ytterbium. The element was discovered in 1794 by Finnish chemist Johan Gadolin (1760—1852). The discovery of yttrium marked the beginning of 100 years of complicated chemical research that resulted in the discovery of 10 new elements. 

The biggest surprise of their study was the discovery of the divalent character of metallic europium and ytterbium. Earlier studies of the light lanthanide (La, Ce, Pr and Nd) and erbium metals indicated that these lanthanides and yttrium were trivalent and so the expectation was that the remaining lanthanides should also be trivalent. Since divalent salts of europium and ytterbium were known in addition to the corresponding trivalent ones, the divalent nature was readily understood in terms of Hund s rules for stable half-filled and completely filled electronic levels (in these cases, 4f and 4f respectively). 

Yttrium asserted its individuality later. Whether Mosander obtained pure terbium or not remains unclear. Erbium had the same fate as didymium. And one more correction in the list of official discovery dates is necessary real yttrium was extracted by Mosander in 1843. Therefore, it is Mosander who stood at the cradle of REEs. 

Known rare-earth minerals were few gadolinite and ce-rite were extremely rare and the other minerals (there were about ten of them) could be likened, as regards their abundance, to museum pieces. Nevertheless, the era of new discoveries had come and the first sprouts appeared on the yttrium tree. Mosander s erbium remained controversial for a long time and only in 1878 did the Swiss scientist J. de Marignac separate a new element from erbium he named it ytterbium also after the village of Ytterby. 

In 1879 the chemical individuality of erbium freed from impurities was proven beyond any doubt and that year rather than 1843 can be considered to be the date of its discovery. Thulium turned out to be pure as well, but holmium s real birth was still ahead. So the yttrium tree branched copi-... 

The magnetic term in the heat capacity is what would be expected from the ferromagnetic spiral (i.e. the cone) structure of erbium (Kaplan 1961) and has been supported by the discovery of a linear spin-wave dispersion law along the c-axis in neutron scattering experiments (Nicklow et al. 1971). 

Discovery Carl Gustaf Mosander in Stockholm in 1842-43 found that Gadolin s yttrium, the first rare earth metal discovered, was composed of three elements. One was allowed to keep the name yttrium, while the two others became terbium and erbium. Thus these new elements also got their names from Ytterby. 

Discovery During 1878-79, PerT. Cleve in Uppsala discovered that erbium contained two other elements. He named them thulium after the old Roman name Thulia for the Furthest North and holmium after Stockholm. Delafontaine and Soret in Switzerland had in fact found lines of a foreign element during the spectral analysis of erbium in 1878. This element, erbium-X or element-X, appeared to be identical with holmium. In tables of discoverers Delafontaine and Soret are mentioned alongside Cleve. 

Discovery J.-C. Marignac in Switzerland discovered Ytterbium in 1878. He investigated erbium and found that the element was not homogenous but contained a new rare earth metal. Once again Ytterby s name was invoked. 

From Figure 17.3 it is clear that the history of discoveries falls into three different periods. The first, about 1800, was the time for the basic discoveries, yttrium and cerium the second, around 1840, resulted in four new elements, erbium, terbium, lanthanum and didymium. Not until the introduction of the spectroscopy in the middle of the 19 century and the development of improved separation techniques did the discoveries enter the third period, 1870-1910. Yet, the last REM, promethium, was not discovered until 1945. Some biographical information about the actual discoverers is given along with the different discovery descriptions below. 

This laboratory, described with such great insight by Johnston, certainly influenced the development of laboratories and examination techniques in other parts of Europe. The fact that the famous German chemist Friedrich Wohler frequently worked as a visiting scientist in the laboratory also contributed to its influence. Carl Gustaf Mosander s substantial work with rare earths around 1840 was also performed here. This led to the discovery of the elements lanthanum, didymium, erbium and terbium. 

Marignac investigated erbium precipitates and found that they were not homogeneous. Two elements were present. One formed red salts with a characteristic absorption spectrum, while compounds of the other element were colorless. The element with the red color kept the name erbium, the other he called ytterbium. The discovery was made in 1878 and separation was possible by addition of hyposulfurous acid to chloride solutions. The erbium precipitated but not the ytterbium. The two elements erbium and ytterbium also appeared to be mixed, and research had to continue. 

Laboratory. The isotope produced was the 20-hour Fm. During 1953 and early 1954, while discovery of elements 99 and 100 was withheld from publication for security reasons, a group from the Nobel Institute of Physics in Stockholm bombarded with O ions, and isolated a 30-min a-emitter, which they ascribed to 100, without claiming discovery of the element. This isotope has since been identified positively, and the 30-min half-life confirmed. The chemical properties of fermium have been studied solely with tracer amounts, and in normal aqueous media only the (III) oxidation state appears to exist. The isotope and heavier isotopes can be produced by intense neutron irradiation of lower elements such as plutonium by a process of successive neutron capture interspersed with beta decays until these mass numbers and atomic numbers are reached. Twenty isotopes and isomers of fermium are known to exist. Fm, with a half-life of about 100.5 days, is the longest lived. °Fm, with a half-life of 30 min, has been shown to be a product of decay of Element 102. It was by chemical identification of Fm that production of Element 102 (nobelium) was confirmed. Fermium would probably have chemical properties resembling erbium. 

One of the authors (PCJ) in Ytterby, Sweden, the site of the discovery of ytterbite and the town after which yttrium, terbium, erbium and ytterbium are named. 

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