Discovery of Spin Glass Behavior in Ln₂Fe₄Sb₅ (Ln = La–Nd and Sm)

Abstract

Single crystals of Ln(2)Fe(4)Sb(5) (Ln = La-Nd and Sm) were grown from an inert Bi flux. Measurements of the single crystal X-ray diffraction revealed that these compounds crystallize in the tetragonal space group I4/mmm with lattice parameters of a ≈ 4 Å, c ≈ 26 Å, V ≈ 500 Å(3), and Z = 2. This crystal structure consists of alternating LnSb(8) square antiprisms and Fe-sublattices composed of nearly equilateral triangles of bonded Fe atoms. These compounds are metallic and display spin glass behavior, which originates from the magnetic interactions within the Fe-sublattice. Specific heat measurements are void of any sharp features that can be interpreted as contributions from phase transitions as is typical for spin glass systems. A large, approximately linear in temperature, contribution to the specific heat of La(2)Fe(4)Sb(5) is observed at low temperatures that we interpret as having a magnetic origin. Herein, we report the synthesis, structure, and physical properties of Ln(2)Fe(4)Sb(5) (Ln = La-Nd and Sm).

The Role of Delocalized Chemical Bonding in Square-Net-Based Topological Semimetals

“…Another noteworthy class of compounds are materials with the idealized composition Ln 2 TM 4 Pn 5 in the La 2 Fe 4 Sb 5 structure type [79][80][81] (t between 0.91 and 0.93; 11 compounds).…”

“…Another noteworthy class of compounds are materials with the idealized composition Ln 2 TM 4 Pn 5 in the La 2 Fe 4 Sb 5 structure type − ( t between 0.91 and 0.93; 11 compounds). These compounds are known to exhibit vacancies in the TM and Pn positions, including flux atoms and itinerant atoms, which have prevented their inclusion in structure catalogues.…”

PbGa4S7: a wide-gap nonlinear optical material

“…In the second approach, inspired by the facts that a series of arsenides and germanides, including LaCo 2 As 2 , 42 Ln 2 Fe 4 Sb 5 , 43 Ce 2 CuGe 6 , 44 and LnCoGe 3 (Ln = Ce, Pr, Nd), 45 could be synthesized from the Bi flux, we tried Bi 2 Q 3 (Q = S, Se) as a flux in the reaction between PbQ and Ga 2 Q 3 . In a typical reaction, powders of PbQ, Ga 2 Q 3 , and Bi 2 Q 3 were mixed in the 1 : 2 : 1 ratio, and then sealed in fused-silica tubes under an Ar atmosphere in a glovebox.…”

An investigation of new infrared nonlinear optical material: BaCdSnSe4, and three new related centrosymmetric compounds: Ba2SnSe4, Mg2GeSe4, and Ba2Ge2S6

“…[9][10][11][12] Among them, the molten flux method has been systematically studied using alkali-metal polychalcogenides, alkali halides or other reagents as the flux, and a large amount of new ternary and quaternary compounds were achieved. [13][14][15][16][17][18][19][20][21][22][23][24] For example, (i) A 2 Hg 3 M 2 S 8 (A = Cs, Rb; M = Sn, Ge), Li 2 PbGeS 4 , Li 2 EuGeS 4 , Na 1.5 Pb 0.75 PSe 4 , AZrPSe 6 (A = K, Rb, and Cs), and A 0.5 Pb 1.75 GeS 4 (A = Li, Na) were successfully synthesized using the alkali polychalcogenide flux method; [13][14][15][16][17] (ii) CsSmGeS 4 , AgLa 3 GeS 7 , Ba 3 AGa 5 Se 10 Cl 2 (A = K, Rb, and Cs) and Ba 4 CuGa 5 Q 12 (Q = S, Se) were obtained with alkali halides as the flux, such as KBr and CsCl, etc. ; [18][19][20][21] (iii) a series of arsenides and germanides, including LaCo 2 As 2 , Ln 2 Fe 4 Sb 5 (Ln = La-Nd and Sm), and Ce 2 CuGe 6 , were syn-thesized in a Bi flux; 22,23 (iv) the IR NLO material PbGa 4 S 7 was not obtained via direct combination reactions of the elements, and it seems to be achieved only in a Bi 2 S 3 flux.…”