Manganese disilicide

From Wikipedia, the free encyclopedia
Manganese disilicide
Кристаллы дисилицида марганца на пластинках кремния.tif
Electron micrograph of MnSi2 stars grown on Si plates
Names
IUPAC name
Manganese disilicide
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.031.606 Edit this at Wikidata
EC Number
  • 234-781-6
  • InChI=1S/Mn.2Si
    Key: FHTCLMVMBMJAEE-UHFFFAOYSA-N
  • [Si]=[Mn]=[Si]
Properties
MnSi2
Molar mass 111.109 g/mol
Appearance gray crystals[1]
Melting point 1,152 °C (2,106 °F; 1,425 K)[1][3] dec.
0.7×10−6 emu/g (MnSi1.72)[2]
Structure
Tetragonal[4]
P4c2 (No. 116), tP44
a = 0.5518 nm, c = 1.7449 nm
4
Hazards
Flash point Non-flammable
Related compounds
Other cations
Cobalt disilicide
Iron disilicide
Titanium disilicide
Related compounds
Manganese monosilicide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N (what is checkY☒N ?)

Manganese disilicide (MnSi2) is an intermetallic compound, a silicide of manganese. It is a non-stoichiometric compound, with a silicon deficiency expressed as MnSi2–x. Crystal structures of many MnSi2–x compounds resemble a chimney ladder and are called Nowotny phases. They include MnSi2 (x=0), Mn4Si7 (x=0.250), Mn11Si19 (x=0.273), Mn15Si26 (x=0.267) and Mn27Si47 (x=0.259). These phases have very similar unit cells whose length varies from 1.75 nm for MnSi2 or Mn4Si7, which have almost the same structures, to 11.8 nm for Mn27Si47.[5]

Mn4Si7 structure

MnSi2–x Nowotny phases have a Mn sublattice with a β-tin structure overlaid with a face-centered cubic Si sublattice. They resemble chimneys of transition metal atoms containing spiraling ladders of Si. These phases are semiconductors with a band gap of 0.4 to 0.9 eV. They exhibit a reasonably high thermoelectric figure of merit ZT ~ 0.8 and have potential applications in thermoelectric generators.[5]

References[edit]

  1. ^ a b Haynes, William M., ed. (2016). CRC Handbook of Chemistry and Physics (97th ed.). CRC Press. p. 4.73. ISBN 9781498754293.
  2. ^ Shinoda, Daizaburo; Asanabe, Sizuo (1966). "Magnetic Properties of Silicides of Iron Group Transition Elements". Journal of the Physical Society of Japan. 21 (3): 555. Bibcode:1966JPSJ...21..555S. doi:10.1143/JPSJ.21.555.
  3. ^ Levinson, Lionel M. (1973). "Investigation of the defect manganese silicide MnnSi2n−m". Journal of Solid State Chemistry. 6 (1): 126–135. Bibcode:1973JSSCh...6..126L. doi:10.1016/0022-4596(73)90212-0.
  4. ^ Shin, Yooleemi; Rhim, Sung Hyon; Duong, Anh Tuan; Nguyen, Van Quang; Hong, Soon Cheol; Cho, Sunglae; Park, Hyun-Min (2015). "New synthesis of MnSi2 thin film and its thermoelectric properties". Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films. 33 (6): 061516. Bibcode:2015JVSTA..33f1516S. doi:10.1116/1.4932515. ISSN 0734-2101.
  5. ^ a b Higgins, Jeremy M.; Schmitt, Andrew L.; Guzei, Ilia A.; Jin, Song (2008). "Higher Manganese Silicide Nanowires of Nowotny Chimney Ladder Phase". Journal of the American Chemical Society. 130 (47): 16086–16094. doi:10.1021/ja8065122.