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Periodic rare earth metals

The very long period is closely similar to the second long period, except for the interpolation of the rare-earth metals. It is interesting that a straight line can be passed through the points for barium, the two bivalent rare-earth metals, and the tetrahedral radii of the heavier elements. [Pg.360]

Figure 4.2. The Periodic Table special collective names. The informal symbols of these families of elements are A = alkali metals, Ae = alcaline earth metals, Ln = lanthanides R = rare earth metals = Sc + Y + lanthanides, An = actinides, Hal = halogens, Chal = chalcogens,... Figure 4.2. The Periodic Table special collective names. The informal symbols of these families of elements are A = alkali metals, Ae = alcaline earth metals, Ln = lanthanides R = rare earth metals = Sc + Y + lanthanides, An = actinides, Hal = halogens, Chal = chalcogens,...
The 3rd group of the Periodic Table (the 1st column within the block of the transition elements) contains the metals scandium, yttrium, lanthanum, and actinium. Lanthanum (atomic number 57) may be considered the earliest member of the family of metals, called lanthanides (general symbol Ln), forming, inside the principal transition series, an inner transition series (up to atomic number 71). Scandium and yttrium together with the lanthanides are also called rare earth metals (general symbol R). [Pg.356]

Table 5.18. Highest melting points (°C) in the alloys of rare earth metals and actinides with compound-forming elements of the 4th and 6th rows of the Periodic Table. See the introduction for the meaning of symbols. [Pg.384]

These problems have of course different weights for the different metals. The high reactivity of the elements on the left-side of the Periodic Table is well-known. On this subject, relevant examples based on rare earth metals and their alloys and compounds are given in a paper by Gschneidner (1993) Metals, alloys and compounds high purities do make a difference The influence of impurity atoms, especially the interstitial elements, on some of the properties of pure rare earth metals and the stabilization of non-equilibrium structures of the metals are there discussed. The effects of impurities on intermetallic and non-metallic R compounds are also considered, including the composition and structure of line compounds, the nominal vs. true composition of a sample and/or of an intermediate phase, the stabilization of non-existent binary phases which correspond to real new ternary phases, etc. A few examples taken from the above-mentioned paper and reported here are especially relevant. They may be useful to highlight typical problems met in preparative intermetallic chemistry. [Pg.552]

Berkelium is a metallic element located in group 11 (IB) of the transuranic subseries of the actinide series. Berkelium is located just below the rare-earth metal terbium in the lanthanide series of the periodic table. Therefore, it has many chemical and physical properties similar to terbium ( Tb). Its isotopes are very reactive and are not found in nature. Only small amounts have been artificially produced in particle accelerators and by alpha and beta decay. [Pg.325]

Schnitzlbaumer, M. (2006) Rare-earth Metal Alkoxides on Periodic Mesoporous Silica. PhD thesis. [Pg.509]

Friend, J. N., The periodic sphere and the position of the rare earth metals. ... [Pg.726]

Hydrogen and the ammonium salts are dealt with in Volume II, along with the Elements of Group I. The position of the rare earth metals in the Periodic Classification has for many years been a source of difficulty. They have all been included in Volume IV, along with the Elements of Group III, as this was found to be the most suitable place for them. [Pg.271]

A compound that is able to influence the relaxation times of water protons has to be paramagnetic. In the Periodic System paramagnetic ions are to be found amongst the transition metals and the rare earth metals (lanthanides). However, it was well known, that the free ions of heavy metals are toxic. Lanthanide ions form soluble complexes with ligands such as phospholipids, amino acids and proteins that are present in plasma. The liver and the skeleton are the major sites of accumulation of free metal ions. Uptake in the liver is mediated by the hepa-tocytes [2]. [Pg.3]

Rare-Earth Metals Coordination Chemistry of the Periodic Table s Footnotes ... [Pg.290]

The rare-earth metals, elements 58 to 71, lying between lanthanum and hafnium, have partially filled 4f orbitals. They are not given places in the form shown but may be accommodated by further expanding the Periodic Table. All of these elements have a principal valence of +3 and certain of them may have +2 or +4 valences also. Descriptions of the chemistry of these metals appear in a number of reference books and more advanced works. [Pg.115]

Aluminium and its Congeners, including the Rare Earth Metals (Group III, of the Periodic Table). By H F V. Little, B.So. (Lond.), A.RC.S, Chief Chemist to Thorium, Ltd. [Pg.378]

Third long period Even seiies. Odd Xe 130 2 Cs 132 81 Ba 137 37 The Rare Earth Metals ... [Pg.278]

News in which he stated the following question (Brauner, 1895) "Where is there a place in the periodic system for the numberless rare-earth metals (true chemical asteroids) the atomic weight of which varies between 140 and 170 / and he wrote ... [Pg.35]

Mechanical milling, 292, 295 Mechanochemical method, 419 Medical applications, 146 Medium-long forms of the periodic table, 81 Melting point of rare-earth metals, 80 MEM. See Maximum entropy method Mendeleev, Dmitrii Ivanovich, 8,37 line, 15 method, 24 methodology, 37 active rare-earth research, 25... [Pg.522]


See other pages where Periodic rare earth metals is mentioned: [Pg.194]    [Pg.324]    [Pg.508]    [Pg.213]    [Pg.340]    [Pg.56]    [Pg.22]    [Pg.2]    [Pg.310]    [Pg.2]    [Pg.504]    [Pg.909]    [Pg.1063]    [Pg.8]    [Pg.269]    [Pg.158]    [Pg.239]    [Pg.2]    [Pg.370]    [Pg.26]    [Pg.65]    [Pg.87]    [Pg.119]   
See also in sourсe #XX -- [ Pg.429 , Pg.430 ]




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