Density rare earth elements

Scandium is a soft, lightweight, silvery-white metal that does not tarnish in air, but over time, it turns yellowish-pink. It resists corrosion. Scandium reacts vigorously with acids, but not water. Scandium has some properties similar to the rare-earth elements. Although its position in group 3 places it at the head of the 17 elements of the lanthanide series of rare-earth metals, scandium, as a metal, is not usually considered a rare-earth. Scandiums melting point is l,54l°C, its boiling point is 2836°C, and its density is 2.989 glctn . 

Samarium is a yellowish metal with a melting point of 1,962°F (1,072°C) and a boiling point of about 3,450°F (1,900°C). Its density is 7.53 grams per cubic centimeter. Samarium is the hardest and most brittle of the rare earth elements. 

Table 1 shows the physico-chemical characteristics of the samples. The results clearly indicate that all zeolites have the same global SAR and approximately the same sodium content. However, the SAR of the framework is much lower for the high rare earth content zeolite, showing that such a high content prevented dealumination. This feet is confirmed by the higher microporous volume of this sample as well as the lower mesoporous specific area. As expected, the samples containing rare earth elements have a lower acid site density. 

Antipcrovskites are known to form with rare earth elements, most notably the series ATTAIN (Af = C c. La. Nd, Pr, Sm [227], Those with the actual perovskite structure are oxynitrides LaWO(, N, 4 and NdWOu N, 4 [22.8] and have been the subject of some theoretical discussion [2291. The magnetic phase transitions can be explained by assuming that the Fermi level lies near a singularity in the electronic density of states [230], XANF.S and heat capacity measurements confirm these magnetic transitions [231, 232]. 

This correlation exists despite any a priori reason why Np should always behave as a rare-earth element where the large orbital contribution unambiguously determines the hyperfine field Hhf. Such a type of relation is less reliable in transition metals due to variations of the localization of the d states, where the spatial extent of the spin density can differ markedly according to bonding conditions. 

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