Chemistry:Mavlyanovite

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Short description: Manganese-silicon mineral
Mavlyanovite
General
CategoryMineral
Formula
(repeating unit)
Mn5Si3
Strunz classification01.BB.05
Dana classification01.01.23.06
Crystal systemHexagonal
Space groupP63/mcm
Unit cella = 6.8971, c = 4.8075, Z = 2; V = 198.05
Structure
Identification
Colourgrey
Fractureconchoidal
Mohs scale hardness7
|re|er}}metallic
Streakdark grey
Diaphaneityopaque
Density6.02

Mavlyanovite is a manganese-silicon mineral with formula Mn5Si3.[2] It was named after Gani Mavlyanov, an Uzbek geologist who lived from 1910 to 1988.

Transition metal silicides represent a rich variety of intermetallic compounds with specific crystal and electronic structures owing to the strong interaction between metals and silicon. Recently, transition metal silicides have gained considerable attention from the scientific community because of their unique physicochemical properties such as high thermal stability, excellent electronic conductivity, low electrical resistivity, high strength, good thermodynamic stability, good oxidation, and corrosion resistance. With these favorable properties, transition metal silicides are potential candidates for various nanotechnological applications such as electronics, spintronics, thermoelectrics, and solar energy harvesting. Among all transition metal silicides, manganese silicides have been investigated extensively because of their complex structural diversity and fascinating physical properties. Manganese silicides possess seven thermodynamically stable phases, namely: MnSi1.7 (tetragonal), MnSi (cubic), Mn5Si3 (hexagonal), Mn5Si2 (tetragonal), Mn3Si (cubic), Mn4Si (rhombohedral), and Mn6Si (rhombohedral). Each of these phases results in different magnetic and thermoelectric properties either in microscopic or microscopic scales. For instance, MnSi is an excellent magnetic contact material for magnetic applications and spintronics such as spin field-effect transistors owing to its simple cubic crystal structure without space inversion symmetry. Among the manganese silicide materials, MnSi1.7, which is a higher manganese silicide, has attracted most interest in the researches for its excellent thermoelectric properties such as low thermal conductivity (2–4 W/m.K), high Seebeck coefficient (>200 mV/K at ~700 K) and estimable figure of merit (up to 0.7–0.8). Mn5Si3 is one of the promising materials for spintronic applications because of its hexagonal structure, and has the potential to create high magnetocrystalline anisotropy with novel spin-electronic properties. In addition, Mn5Si3 has a high melting point of 2800 K, indicating that it is a favorable candidate for high-temperature structural applications.[3]

References

  1. Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine 85 (3): 291–320. doi:10.1180/mgm.2021.43. Bibcode2021MinM...85..291W. 
  2. Yusupov, R. G.; Stanley, C. J.; Welch, M. D.; Spratt, J.; Cressey, G.; Rumsey, M. S.; Seltmann, R.; Igamberdiev, E. (February 2009). "Mavlyanovite, Mn 5 Si 3 : a new mineral species from a lamproite diatreme, Chatkal Ridge, Uzbekistan". Mineralogical Magazine 73 (1): 43–50. doi:10.1180/minmag.2009.073.1.43. 
  3. Sadri, Rad (15 January 2021). "Controlled physical properties and growth mechanism of manganese silicide nanorods". Journal of Alloys and Compounds 851: 156693. doi:10.1016/j.jallcom.2020.156693. https://www.sciencedirect.com/science/article/abs/pii/S0925838820330577.