Erbium physical properties

Carl Gustaf Mosander, a Swedish chemist, successfully separated two rare-earths from a sample of lanthanum found in the mineral gadolinite. He then tried the same procedure with the rare-earth yttria. He was successful in separating this rare-earth into three separate rare-earths with similar names yttia, erbia, and terbia. For the next 50 years scientists confused these three elements because of their similar names and very similar chemical and physical properties. Erbia and terbia were switched around, and for some time the two rare-earths were mixed up. The confusion was settled ostensibly in 1877 when the chemistry profession had the final say in the matter. However, they also got it wrong. What we know today as erbium was originally terbium, and terbium was erbium. 

First ionization potential 6.10 eV second 11.93 eV. Ionic radius Erl+ 0.881 A. Metallic radius 1.758 A. Other important physical properties of erbium are given under Rare-Earth Elements and Metals. 

It is possible to include yttrium among the rare earths, because of its properties, which are rather like those of some of the rare earths. For instance, when we express a physical property of the sulfides as a function of the ionic radii of the metals, the yttrium sulfide normally lies among the rare earth series, without any discontinuity, between dysprosium and erbium sulfides. 

Lanthanide elements (referred to as Ln) have atomic numbers that range from 57 to 71. They are lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu). With the inclusion of scandium (Sc) and yttrium (Y), which are in the same subgroup, this total of 17 elements are referred to as the rare earth elements (RE). They are similar in some aspects but very different in many others. Based on the electronic configuration of the rare earth elements, in this chapter we will discuss the lanthanide contraction phenomenon and the consequential effects on the chemical and physical properties of these elements. The coordination chemistry of lanthanide complexes containing small inorganic ligands is also briefly introduced here [1-5]. 

The materials derived from YBa2Cu307 by replacing yttrium with other rare earth elements (lutetium, ytterbium, thulium, erbium, hohnium, dysprosium, gadolinium, europium, samarium, neodymium, lanthanum) are also superconductors, with r, s of 88 to 96 K. The crystal structures of RBa2Cu307 are almost the same as those of YBa2Cu307. The lattice constant is slightly different for the different ionic radii of the rare earth elements, and yet their chemical and physical properties are almost the same as those of YBa2Cu307. 

The last problem is relative to the crystallographie phases. They are often deduced from electron diffraction patterns (EDP s). Various phenomena whieh oeeurred in the course of the study of thin samples are sometimes badly known, or else the patterns can be misinterpreted and the indexation becomes wholly wrong. Reeently Z. Li et al. (1988) have claimed to the formation of new polymorphic erbium oxide phases. These were in fact the well-known ErH2, C- and B-Er203 compounds (Gasgnier 1980, 1990). Other misinterpretations result from decided opinions on chemical reactivity, phase transitions, compound formation (as Lu(OH)4 for example) (Gasgnier 1991). .. and/or on disorder between two crystallographic phases. The rare earth series display basie chemical and physical properties which are now well established. Moreover, the new micro- (and even nano-) analysis apparatus should be used in a systematic way to insure accurate determination of the specific properties of the materials. 

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. 

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