మూస:సమేరియం మూలకము

Samarium, 00Sm
Samarium
Pronunciation/səˈmɛəriəm/ (-MAIR-ee-əm)
Appearancesilvery white
Standard atomic weight Ar°(Sm)
Samarium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Ununtrium Flerovium Ununpentium Livermorium Ununseptium Ununoctium


Sm

Pu
promethiumsamariumeuropium
Groupమూస:Infobox element/symbol-to-group/format
Periodperiod 6
Block  f-block
Electron configuration[Xe] 4f6 6s2
Electrons per shell2, 8, 18, 24, 8, 2
Physical properties
Phase at STPsolid
Melting point1345 K ​(1072 °C, ​1962 °F)
Boiling point2173 K ​(1900 °C, ​3452 °F)
Density (near r.t.)7.52 g/cm3
when liquid (at m.p.)7.16 g/cm3
Heat of fusion8.62 kJ/mol
Heat of vaporization192 kJ/mol
Molar heat capacity29.54 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 1001 1106 1240 (1421) (1675) (2061)
Atomic properties
Oxidation states0,[3] +1,[4] +2, +3 (a mildly basic oxide)
ElectronegativityPauling scale: 1.17
Ionization energies
  • 1st: 544.5 kJ/mol
  • 2nd: 1070 kJ/mol
  • 3rd: 2260 kJ/mol
Atomic radiusempirical: 180 pm
Covalent radius198±8 pm
Color lines in a spectral range
Spectral lines of samarium
Other properties
Natural occurrenceprimordial
Crystal structurerhombohedral
Rhombohedral crystal structure for samarium
Speed of sound thin rod2130 m/s (at 20 °C)
Thermal expansion(r.t.) (α, poly) 12.7 µm/(m⋅K)
Thermal conductivity13.3 W/(m⋅K)
Electrical resistivity(r.t.) (α, poly) 0.940 µΩ⋅m
Magnetic orderingparamagnetic[5]
Young's modulusα form: 49.7 GPa
Shear modulusα form: 19.5 GPa
Bulk modulusα form: 37.8 GPa
Poisson ratioα form: 0.274
Vickers hardness412 MPa
Brinell hardness441 MPa
CAS Number7440-19-9
History
Namingafter the mineral samarskite (itself named after Vasili Samarsky-Bykhovets)
Discovery and first isolationLecoq de Boisbaudran (1879)
Isotopes of samarium
Template:infobox samarium isotopes does not exist
 Category: Samarium
| references

References

  1. "Standard Atomic Weights: Samarium". CIAAW. 2005.
  2. Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; et al. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry (in ఇంగ్లీష్). doi:10.1515/pac-2019-0603. ISSN 1365-3075.
  3. Yttrium and all lanthanides except Ce and Pm have been observed in the oxidation state 0 in bis(1,3,5-tri-t-butylbenzene) complexes, see Cloke, F. Geoffrey N. (1993). "Zero Oxidation State Compounds of Scandium, Yttrium, and the Lanthanides". Chem. Soc. Rev. 22: 17–24. doi:10.1039/CS9932200017. and Arnold, Polly L.; Petrukhina, Marina A.; Bochenkov, Vladimir E.; Shabatina, Tatyana I.; Zagorskii, Vyacheslav V.; Cloke (2003-12-15). "Arene complexation of Sm, Eu, Tm and Yb atoms: a variable temperature spectroscopic investigation". Journal of Organometallic Chemistry. 688 (1–2): 49–55. doi:10.1016/j.jorganchem.2003.08.028.
  4. SmB6- cluster anion has been reported and contains Sm in rare oxidation state of +1; see Paul, J. Robinson; Xinxing, Zhang; Tyrel, McQueen; Kit, H. Bowen; Anastassia, N. Alexandrova (2017). "SmB6 Cluster Anion: Covalency Involving f Orbitals". J. Phys. Chem. A 2017, 121, 8, 1849–1854. 121 (8): 1849–1854. doi:10.1021/acs.jpca.7b00247. PMID 28182423. S2CID 3723987..
  5. Magnetic susceptibility of the elements and inorganic compounds, in Handbook of Chemistry and Physics 81st edition, CRC press.