12032-89-2Relevant articles and documents
Noncollinear magnetic structure of MnTe2
Burlet,Ressouche,Malaman,Welter,Sanchez,Vulliet
, p. 14013 - 14018 (1997)
The crystallographic and magnetic properties of the MnTe2 compound have been investigated by 125Te Moessbauer spectroscopy and by neutron diffraction on both powder and single-crystal samples. From TN down to 4.2 K, the si
The new sodium tellurido manganates(II) Na2Mn2Te3, Na2Mn3Te4, Na2AMnTe3 (A=K, Rb), and NaCsMnTe2
Langenmaier, Michael,R?hr, Caroline
, (2019)
A series of new sodium and mixed Na/A (A = K, Rb, Cs) tellurido manganates have been synthesized from melts of the pure elements (or MnTe) at maximum temperatures of 600-1000°C. The monoclinic crystal structures of the two pure sodium salts Na2Mn2Te3 (space group C2/c, a = 1653.68(2), b = 1482.57(2), c = 773.620(10) pm, β = 117.52°, Z = 8, R1 = 0.0225) and Na2Mn3Te4 (space group C2/m, a = 1701.99(3), b = 438.741(8), c = 691.226(12) pm, β = 90.3171(8)°, Z = 2, R1 = 0.0270) are both based on a hexagonal close packed Te2- arrangement. Na2Mn2Te3 is isotypic with Na2Mn2S3 and Na2Mn2Se3 and contains layers of [MnTe4] tetrahedra, which are connected via common edges to form tetramers [Mn4Te6]. These tetramers are further connected via μ3-Te atoms. Na2Mn3Te4 crystallizes in a new structure type, recently also reported for the selenido salt Na2Mn3Se4. Mn(2) forms ribbons of vertex-sharing dinuclear units ∞1[Te2/2MnTe2MnTe2/2] USD_infty ^1[{rm{T}}{{rm{e}}_{2/2}}{rm{MnT}}{{rm{e}}_2}{rm{MnT}}{{rm{e}}_{2/2}}]USD running along the short b axis of the monoclinic cell. The Te atoms of these ribbons are also the ligands of edge-sharing [Mn(1)Te6] chains of octahedra. Similar to Na2Mn2Te3, the Na+ cations are octahedrally coordinated and the cations occupy tetrahedral (Mn2+) and octahedral (Na+, Mn2+) voids in the close Te2- packing. The isotypic K/Rb salts Na2AMnTe3 crystallize in a new structure type (orthorhombic, space group Pmc21, a = 1069.70(4)/1064.34(2), b = 1350.24(5)/1350.47(3), c = 1238.82(4)/1236.94(3) pm, Z = 4, R1 = 0.0445/0.0210). In contrast to the simple formula indicating a Mn(III) compound, the complex structure contains one layer consisting of undulated chains of edge-sharing tetrahedra ∞1[MnIITe4/2] USD_infty ^1[{rm{M}}{{rm{n}}^{{rm{II}}}}{rm{T}}{{rm{e}}_{4/2}}]USD separated by free ditelluride dumbbells [Te2]2- and a second layer containing a complex chain of edge- A nd vertex-sharing [MnIITe4] tetrahedra, in which Mn(II) is coordinated to μ1- A nd μ2-Te2- ligands and an η1-ditellurido ligand. The cesium salt NaCsMnTe2 (orthorhombic, space group Cccm, a = 694.21(2), b = 1536.57(4), c = 664.47(2) pm, Z = 4, R1 = 0.0131) likewise forms a new structure type, which is an ordered superstructure of ThCr2Si2. Linear chains ∞1[MnTe4/2] USD_infty ^1[{rm{MnT}}{{rm{e}}_{4/2}}]USD of edge-sharing tetrahedra are connected with similar chains ∞1[NaTe4/2] USD_infty ^1[{rm{NaT}}{{rm{e}}_{4/2}}]USD to form [NaMnTe2] layers. The larger alkali cations Cs+ between the layers exhibit a cubic (CN = 8) coordination.
THERMAL EXPANSION OF MnTe2.
Kasai,Waki,Ogawa
, p. 3303 - 3307 (1981)
The thermal expansion of MnTe//2 has been measured. A small anomaly in thermal expansion has been observed at 60 K, which is probably due to a change of internal parameter of crystal. The coefficient of thermal expansion has been separated into lattice, magnetic and Schottky contributions. Results are discussed.
Elliot, N.
, p. 1958 - 1962 (1937)
Syntheses, molecular structures, and thermal decomposition of cyclopentadienyldicarbonylmanganese chalcogenide derivatives
Pasynskii,Grigoriev,Torubaev,Blokhin,Shapovalov,Dobrokhotova,Novotortsev
, p. 2689 - 2700 (2003)
Transmetallation of the dichalcogenide complexes [CpMn(CO) 2]2(μ-X2) (X = S or Se) with M(CO) 5(thf) (M = Cr or W) afforded new heterometallic complexes CpMn(CO)2(μ-Se2)Cr(CO)5,
Synthesis and structures of new layered ternary manganese tellurides: AMnTe2 (A = K, Rb, Cs), Na3Mn4Te6, and NaMn1.56Te2
Kim, Joonyeong,Wang, Chwanchin,Hughbanks, Timothy
, p. 235 - 242 (1999)
The synthesis and crystal structures of new ternary manganese tellurides, AMnTe2 (A = K, Rb, Cs), Na3Mn4Te6, and NaMn1.56Te2, are reported. These compounds are synthesized by solid-state reaction and cation exchange techniques in sealed Nb tubes. The single-crystal structures of AMnTe2 (A = K, Rb), Na3Mn4Te6, and NaMn1.56Te2 have been determined; KMnTe2: a = 4.5110(4) ?, c = 14.909(2) ?, I4m2 (No. 119, Z = 2); RbMnTe2: a = 4.539(1) ?, c = 15.055(2) ?, I4?m2 (No. 119, Z = 2); Na3Mn4Te6: a = 8.274(4) ?, b = 14.083(6) ?, c = 7.608(6) ? β = 91.97(4)°, C2/m (No. 12, Z = 2); NaMn1.56Te2: a = 4.4973(8) ?, c = 7.638(2) ?, P3?m1 (No. 164, Z = 1). The fundamental building blocks of the title compounds are MnTe4 tetrahedra. AMnTe2 (A = K, Rb, Cs) are isostructural with TlFeS2, consisting of layers built up by four corner-shared MnTe4 tetrahedra. Manganese telluride layers in Na3Mn4Te6 consist of two hexagonal nets of Te atoms between which two-thirds of the tetrahedral interstices are filled with Mn atoms to form two 63 honeycomb nets. NaMn1.56Te2 adopts a defective CaAl2Si2 structure type, in which Mn atoms partially and randomly occupy 78% of tetrahedral sites. Temperature-dependent magnetic susceptibilities measurements show that AMnTe2 (A = K, Rb, Cs) exhibit Curie-Weiss paramagnetism, whereas Na3Mn4Te6 and NaMn1.56Te2 show paramagnetism with a weak dependence on temperature.
Magnetic and electrical properties of manganese telluride
Uchida, Enji,Kondoh, Hisamoto,Fukuoka, Nobuo
, p. 27 - 32 (1956)
The temperature dependence of the susceptibility of the antiferromagnetic compound MnTe was measured over a range of temperature between liquid nitrogen temperature and 720°C. An abrupt change in slope and a maximum of the susceptibility curve were found at 37°C and at 55°C respectively. These results are compared with the observed Neel temperatures previously reported by Squire and by Serre. A thermal hysteresis was also found above the Neel temperature, relating to the heat history of the specimen. It is shown that the susceptibility of MnTe1+x (O≤x≤1), where x is the excess content of tellurium, is explicable in terms of two phases, MnTe and MnTe2 which possess different susceptibilities. The electrical properties, i.e., the resistivity, the thermo-emf and the Hall emf, were measured as functions of temperature. Evidence was found of anomalous behaviours at the Neel temperature for them. A large thermal hysteresis of the resistivity is also found above the Neel temperature, which suggests a change of the crystal structure at about 130°C.
Delves, R. T.,Lewis, B.
, p. 549 - 556 (1963)
Pasternak, M.,Spijkervet, A. L.
, p. 574 - 579 (1969)
Synthesis and crystal structure of manganese-tris(1,2-ethanediamine)tetratelluride [Mn(en)3]Te4 exhibiting intermolecular interactions between the tetratelluride anions
Wendland, Frank,Naether, Christian,Bensch, Wolfgang
, p. 456 - 461 (2008/10/08)
Air-sensitive black crystals of the new compound [Mn(en)3]Te4 were synthesized by reacting MnCl2 · 4 H2O, K2Te3 and elemental Te in 1,2-ethanediamine (en) under solvothermal conditions at 433 K. The compound crystallizes in the monoclinic space group P21/n with lattice parameters a = 839.51(7) pm, b = 1551.3(1) pm, c = 1432.6(1) pm, and β = 90.28(2)°. Isolated [Mn(en)3]2+ cations and Te42- anions are arranged in an alternating fashion parallel to the crystallographic b-axis. One terminal Te atom of the Te42- anions exhibits a short intermolecular contact to a neighboured anion thus forming Teg4- anions. A slightly longer interionic Te ... Te separation is observed between two of the inner Te atoms of neighboured Te84- anions. Taking these longer separations into account infinite Te-chains are formed running parallel to [001]. The intermolecular Te ... Te interactions affect the Te-Te bond lengths within the Te42- anion leading to a lengthening of the average Te-Te distance. Short N-H ... Te distances indicate hydrogen bonding between the cations and anions. DTA-TG measurements show that at 441 K the material decomposes in one step. The resulting crystalline material consists of MnTe2 and Te.
