Nothing Special   »   [go: up one dir, main page]

Samarium tetraboride is a binary inorganic compound of samarium and boron with the formula SmB4. It forms black crystals.

Samarium tetraboride
Names
IUPAC name
Samarium tetraboride
Identifiers
3D model (JSmol)
  • InChI=1S/4B.Sm
    Key: IXWQBERMPYCDNG-UHFFFAOYSA-N
  • [Sm].[B].[B].[B].[B]
Properties
SmB4
Molar mass 193.60 g/mol
Density 6.1 g/cm3
Melting point 2,400 °C (4,350 °F; 2,670 K)
Related compounds
Related compounds
Samarium hexaboride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Preparation

edit

Samarium tetraboride can be prepared from directly reacting samarium and boron at 2400 °C:

Sm + 4B → SmB4

Physical properties

edit

Samarium tetraboride forms crystals of the orthorhombic crystal system, space group P4/mbm, cell parameters a = 0.7174 nm, c = 0.40696 nm, Z = 4, and a structure like thorium tetraboride.[1][2][3][4][5]

The compound is formed by a peritectic reaction at a temperature of 2400 °C.[1]

At temperatures of 25 K and 7 K, magnetic transitions occur in the compound.[6]

References

edit
  1. ^ a b Диаграммы состояния двойных металлических систем. Vol. 1. М.: Машиностроение. 1996. ISBN 5-217-02688-X. {{cite book}}: Unknown parameter |agency= ignored (help)
  2. ^ Самсонов Г.В., Серебрякова Т.И., Неронов В.А. (1975). Бориды. М.: Атомиздат.{{cite book}}: CS1 maint: multiple names: authors list (link)
  3. ^ Predel, B. (2012), Predel, B. (ed.), "B - Sm (Boron - Samarium): phase equilibria, crystallographic and thermodynamic data of binary alloys", B - Ba … Cu - Zr, vol. 12B, Berlin, Heidelberg: Springer Berlin Heidelberg, p. 73, doi:10.1007/978-3-540-44756-6_37, ISBN 978-3-540-44753-5, retrieved 2024-05-15
  4. ^ Predel, B. (1992), Madelung, O. (ed.), "B-Sm (Boron-Samarium)", B-Ba – C-Zr, Landolt-Börnstein - Group IV Physical Chemistry, vol. 5b, Berlin/Heidelberg: Springer-Verlag, pp. 1–2, doi:10.1007/10040476_390, ISBN 978-3-540-55115-7, retrieved 2024-05-15
  5. ^ Liao, P. K.; Spear, K. E.; Schlesinger, M. E. (Aug 1996). "The B-Sm (boron-samarium) system". Journal of Phase Equilibria. 17 (4): 347–350. doi:10.1007/BF02665562. ISSN 1054-9714.
  6. ^ Kim, J. Y.; Sung, N. H.; Kang, B. Y.; Kim, M. S.; Cho, B. K.; Rhyee, Jong-Soo (2010-05-01). "Magnetic anisotropy and magnon gap state of SmB4 single crystal". Journal of Applied Physics. 107 (9). doi:10.1063/1.3365061. ISSN 0021-8979.