K and Ba distribution in the structures of the clathrate compounds KxBa16−x(Ga,Sn)136 (x = 0.8, 4.4, and 12.9) and KxBa8−x(Ga,Sn)46 (x = 0.3)

Studies of the K–Ba–Ga–Sn system produced the clathrate compounds K_0.8(2)Ba_15.2(2)Ga_31.0(5)Sn_105.0(5) [a = 17.0178 (4) Å], K_4.3(3)Ba_11.7(3)Ga_27.4(4)Sn_108.6(4) [a = 17.0709 (6) Å] and K_12.9(2)Ba_3.1(2)Ga_19.5(4)Sn_116.5(4) [a = 17.1946 (8) Å], with the type‐II structure (cubic, space group Fdm), and K_7.7(1)Ba_0.3(1)Ga_8.3(4)Sn_37.7(4) [a = 11.9447 (4) Å], with the type‐I structure (cubic, space group Pmn). For the type‐II structures, only the smaller (Ga,Sn)₂₄ pentagonal dodecahedral cages are filled, while the (Ga,Sn)₂₈ hexakaidecahedral cages remain empty. The unit‐cell volume is directly correlated with the K:Ba ratio, since an increasing amount of monovalent K occupying the cages causes a decreasing substitution of the smaller Ga in the framework. All three formulae have an electron count that is in good agreement with the Zintl–Klemm rules. For the type‐I compound, all framework sites are occupied by a mixture of Ga and Sn atoms, with Ga showing a preference for Wyckoff site 6c. The (Ga,Sn)₂₀ pentagonal dodecahedral cages are occupied by statistically disordered K and Ba atoms, while the (Ga,Sn)₂₄ tetrakaidecahedral cages encapsulate only K atoms. Large anisotropic displacement parameters for K in the latter cages suggest an off‐centering of the guest atoms.     

Ni2Sn2Zn from single‐crystal X‐ray diffraction

Dinickel ditin zinc, Ni₂Sn₂Zn, crystallizes in the cubic space group , with a lattice parameter of a = 8.845 (1) Å and with all atoms occupying special positions. The crystal structure exhibits pronounced similarities with that of the quaternary compound Ni_5.20Sn_8.7Zn_4.16Cu_1.04. It shares structural features with other compounds in the Ni–Sn–Zn system, such as Ni₅Sn₄Zn and Ni₃Sn₂.     

Bridging chlorides and hydroxides: syntheses and crystal structures of binuclear and tetranuclear NiII complexes derived from a reduced Schiff-base ligand 2-(2-pyridylmethylamino)ethanesulfonic acid

Two complexes, [Ni(pmt)(Cl)] (1) and [Ni₄(pmt)₄(OH)₄]·8H₂O (2) [Hpmt = 2-(2-pyridylmethylamino)ethanesulfonic acid], were synthesized by different experimental methods in methanol-water mixed solution. Compound 1 crystallizes in triclinic, space group P?1 with unit cell parameters: a = 8.315(2) Å, b = 8.383(2) Å, c = 9.128(2) Å, α = 103.654(2)°, β = 98.125(2)°, γ = 113.154(2)°, V = 548.6(2) ų, Z = 2. A pair of chlorides is μ ₂-bridges linking two Ni^II atoms in forming binuclear complex 1. The coordination environment at Ni^II is distorted square-pyramidal geometry. Compound (2) belongs to monoclinic, space group C2/c, with a = 16.5168(15) Å, b = 18.3718(17) Å, c = 17.5473(16) Å, α = γ = 90°, β = 93.3820(10)°, V = 5315.3(8) ų, Z = 4. Four hydroxides are μ ₃-bridges joining four Ni^II atoms to generate a cubic framework as a tetranuclear complex. The configuration at each Ni^II is distorted octahedral. Both π–π stacking of pyridine rings and intermolecular hydrogen bonds stabilize the solid state structures for 1 and 2.     

Structural chemistry of organotin carboxylates XV. Diorganostannate esters of dicyclohexylammonium hydrogen oxalate. Synthesis,crystal structure and in vitro antitumour activity of bis(dicyclohexyl-ammonium) bisoxalatodi-n-butylstannate and bis(dicyclohexylammonium) μ-oxalatobis(aquadi-n-butyloxalatostannate)

Dicyclohexylamine, oxalic acid dihydrate and di-n-butyltin oxide were reacted in 2:2:1 or 2:3:2 stoichiometries in ethanol solution to yield, respectively bis(dicyclohexylammonium) bisoxalatodi-n-butylstannate (1) and bis(dicyclohexylammonium) μ-oxalatobis(aquadi-n-butyloxalatostannate) (2); the hydrate was also obtained upon recrystallization of 1 from moist acetonitrile solution. The crystal structures of the two ammonium stannates have been determined at room temperature. In 1, the tin atom in the dianion exists in a skewtrapezoidal bipyramidal geometry with the basal plane being defined by two bidentate oxalate ligands; each ligand forms asymmetric Sn? O bonds [Sn? O 2.348(4), 2.110(4) Å and 2.112(4), 2.363(4) Å]. The apical sites are occupied by the two organo groups disposed over the weaker Sn? O bonds. In 2, the two tin centres of the dianion are connected via a tetradentate oxalate ligand situated about a centre of inversion and each tin atom exists in a pentagonal bipyramidal geometry. The pentagonal plane is defined by four oxygen atoms, two from the central ligand [Sn? O 2.282(4), 2.473(4)Å] and two from a ‘terminal’ oxalate ligand [Sn? O 2.239(4), 2.210(4)Å], and the fifth site is occupied by a water molecule of crystallization [Sn? O 2.422(4)Å]; the apical sites are filled by the n-butyl groups. Both compounds feature extended hydrogen-bonded networks involving the oxygen atoms of the dianion and the N-bound hydrogen atoms. Crystals of 1 are monoclinic, space group P2₁/n, with cell dimensions a = 13.408(3), b = 22.461(4), c = 13.996(2)Å, β = 100.97(2)^°; full-matrix least-squares refinement on 3305 reflections with I≥2.5σ(I) converged to R = 0.042 and R_w = 0.046. Crystals of 2 are monoclinic, space group P2₁/n, a = 13.729(3), b = 14.694(2), c = 14.889(2)Å, β = 104.83(2)^º; refinement on 2093 reflections converged to R = 0.030 and R_w = 0.031. The two di-n-butylstannates were screened in vitro against the mammary MCF-7 and WiDr colon carcinoma cell lines, and were found to be as active as cisplatin, a clinically used antineoplastic drug.     

The crystal structure of Mg51Zn20

The crystal structure of Mg₅₁Zn₂₀, a phase designated conventionally as “Mg₇Zn₃,” has been determined by the single-crystal X-ray diffraction method. It was solved by the examination of a Patterson synthesis, and refined by the ordinary Fourier and least-squares method; the R value obtained was 4.8% for 1167 observed reflections. The crystal is orthorhombic, space group Immm, with a = 14.083(3), b = 14.486(3), c = 14.025(3) Å, and Z = 2. There are 18 independent atomic sites, Zn1Zn6, Mg1Mg10, A, and B, and the last two sites are statistically occupied by Zn and Mg atoms with the occupancies; 0.46(2)Zn7 + 0.52(2)Mg11 and 0.24(2)Zn8 + 0.74(2)Mg12, for A and B, respectively. The structure of the crystal is described as an arrangement of icosahedral coordination polyhedra, to which all the atomic sites but Zn3 site belong. In this arrangement the Zn atoms other than the Zn3 and Zn8(B) center the icosahedral coordination polyhedra with coordination number 12. The Zn3, Zn8 atoms, and all the Mg atoms except Mg11(A) are located at the centers of various coordination polyhedra with the coordination numbers from 11 to 15. The distances between neighboring atoms are 2.71–3.07, 2.82–3.65, and 2.60–3.20 Å for ZnZn, MgMg, and ZnMg, respectively.     

Synthese und Kristallstrukturen ternärer Phosphide und Arsenide des Rhodiums und Iridiums

Ternary Phosphides and Arsenides of Rhodium and Iridium: Synthesis and Crystal Structures Single crystals of eight new compounds were prepared by heating mixtures of the elements in a lead flux. They were investigated by X‐ray methods. Ca₂Ir₁₂P₇ (a = 9.512(1), c = 3.923(1) Å)is an additional representative of the Zr₂Rh₁₂P₇ type structure, micro domains required refinements of the structural parameters in space group P6₃/m. Ca₅Rh₁₉P₁₂ (a = 12.592(1), c = 3.882(1) Å) and Ca₅Ir₁₉P₁₂ (a = 12.577(2), c = 3.954(1) Å) crystallize with the Ho₅Ni₁₉P₁₂ type structure (P6¯2m; Z = 1), whereas the compounds A₆Rh₃₀X₁₉ form a slightly modified structure of the Yb₆Co₃₀P₁₉ type. The lattice constants are: Ca₆Rh₃₀P₁₉: a = 15.532(1) Å, c = 3.784(1) Å Sr₆Rh₃₀As₁₉: a = 16.135(2) Å, c = 3.916(1) Å Eu₆Rh₃₀P₁₉: a = 15.566(1) Å, c = 3.821(1) Å Eu₆Rh₃₀As₁₉: a = 16.124(1) Å, c =5 3.903(3) Å Yb₆Rh₃₀P₁₉: a = 5 15.508(1) Å, c =5 3.770(1) Å Because one of the four non‐metal atoms, located on different crystallographic sites, is disordered along [001] micro domains are formed. Therefore the parameters were not refined in space group P6¯ (Yb₆Rh₃₀P₁₉ type), but in space group P6₃/m. The metal:non‐metal ratio of all compounds is in the range of 2:1. Accordingly most of the non‐metal atoms are coordinated by nine metal atoms, which form tricapped trigonal prisms. These polyhedra are combined with each other in a different way.     

Synthetic and structural chemistry of nickel(II) complexes containing dithiolato and phosphine ligands I. Preparation and crystal structure of Ni2(PPh3)2(edt)2

A nickel(II) complex containing both dithiolato and phosphine ligands, Ni₂(PPh₃)₂(edt)₂ (edt = SCH₂CH₂S^2-), has been prepared and characterized by X-ray diffration. The complex crystallizes in the triclinic system, space group P-1, with a = 10.693(3), b = 17.457 (6), c = 10.606 (3) Å, α = 102.84(2), β = 96.49 (2), γ = 82.56(3); V = 1906.8 ų; D_c = 1.439 g·cm^?3 for Z = 2; the final conventional R was 0.052 based on 3338 observed reflections. Nickel atoms are linked by two sulfur atoms from two edt ligands with the Ni—Ni distance of 2.893 Å, and each Ni atom is coordinated by one phosphorus atom and three sulfur atoms with a square-planar geometry, where the average length of Ni—S bond is 2.180 Å and Ni—P bond 2.188 Å. The UV-Vis and ¹H NMR spectra have also been recorded.     

Synthesis,characterization and in-vitro antitumour activity of dibutyltin carboxylates involving the perfluorophenyl moiety: Crystal structure of the dimeric bis[(4-fluoro- and pentafluoro-benzoato)di-n-butyltin] oxides

Crystal structure determinations of {[(F₅C₆COO)Bu₂Sn]₂O}₂ and {[(4-F-C₆H₄COO)-Bu₂Sn]₂O}₂ show that the structures are similar and feature central Bu₄Sn₂O₂ units with two Bu₂Sn groups connected by bridging oxygen atoms. Each pair of exo- and endo-cyclic tin atoms is linked by an almost symmetrically bridging carboxylate group, with the two remaining groups attached to the exocyclic tin atom only. Crystals of {[(F₅C₆COO)Bu₂Sn]₂O}₂ are triclinic, space group P1, with unit cell dimensions a = 12.425(3) Å, b = 13.090(5) Å, c = 11.697(3) Å, α = 95.31(3)°, β = 93.28(2)°, γ = 113.01(2)°, V = 1734(1) ų, Z = 1. Crystals of {[(4-F-C₆H₄COO)Bu₂Sn]₂O}₂, are also triclinic, space group PI, a = 12.599(6) Å, b= 25.359(4) Å, c = 11.480(4) Å, α = 91.44(3)°, β = 114.77(3)°, γ=97.43(3)°, V=3289(2) ų, Z=2. The structures were refined to final R= 0.046, R_w = 0.046 for 4312 reflections with I≥ 3.0 σ(l) for {[(F₅C₆COO)Bu₂Sn]₂O}₂ and R=0.061, R_w=0.068 for 4112 reflections with l≥3.0 σ(l for {[(4-F-C₆H₄COO)Bu₂Sn]₂O}₂.     

Die Kristallstruktur des 1 : 1-Adduktes zwischen Antimontrichlorid und Diphenylammoniumchlorid,SbCl3 · (C6H5)2NH2+Cl−

The Crystal Structure of the 1:1 Addition Compound between Antimony Trichloride and Diphenylammonium Chloride, SbCl₃ · (C₆H₅)₂NH₂⁺Cl^? The 1:1 addition compound between antimony trichloride and diphenylammoniumchloride SbCl₃ · (C₆H₅)₂NH₂⁺Cl^? crystallizes in the monoclinic space group P2₁/n with a = 5.668(8), b = 20.480(12), c = 14.448(17) Å, β = 110.4(1)° and Z = 4 formula units. Chains of SbCl₃ molecules and anion cation chains are bridged by Cl ions and form square tubes. The coordination of the Sb atoms by Cl atoms by Cl atoms and Cl ions is distorted octahedral. Mean distances are Sb? Cl = 2.37 Å for Sb? Cl (3×), 3.09 Å for Sb…Cl^? (2×) and 3.42 Å for Sb…Cl (1×). The Sb…Cl^? contacts and hydrogen bonds NH…Cl^? at 3.15 Å generate tetrahedral coordination of the Cl ions.     

Neue Zinn‐reiche Stannide der Systeme AII‐Al‐Sn (AII = Ca,Sr, Ba)

New Tin‐rich Stannides of the Systems A^II‐Al‐Sn (A^II = Ca, Sr, Ba) Four new tin‐rich intermetallics of the ternary systems Ca/Sr/Ba‐Al‐Sn were synthesized from stoichiometric amounts of the elements at maximum temperatures of 1200 °C. Their crystal structures, representing two new types, have been determined using single crystal x‐ray diffraction. Close to the 1:1 composition, the structures of the two isotypic compounds A₁₈[Al₄(Al/Sn)₂Sn₄][Sn₄][Sn]₂ (overall composition A₉M₈; A = Sr/Ba, tetragonal, space group P4/mbm, a = 1325.9(1)/1378.6(1), c = 1272.8(2)/1305.4(1) pm, Z = 4, R1 = 0.0430/0.0293) contain three different anionic Sn/Al building units: Isolated Sn atoms (motif I) coordinated by the alkaline earth cations only (comparable to Ca₂Sn), linear Sn chains (II), which are comparable to the anions in trielides related to the W₅Si₃ structure type and finally octahedral clusters [Al₄M₂Sn₄] (III), composed of four Al atoms forming the center plane, two statistically occupied Al/Sn atoms at the apexes and four exohedral Sn attached to Al. Close to the AM₂ composition, two isotypic tin‐rich intermetallics A₉[Al₃Sn₂][(Sn/Al)₄]Sn₆ (overall composition A₉M₁₅; A = Ca/Sr; space group C2/m, a = 2175.2(1)/2231.0(2), b = 1210.8(1)/1247.0(1), c = 1007.4(1)/1042.0(2) pm, β = 103.38(1)/103.42(1)°, Z = 2, R1 = 0.0541/0.0378) are formed. Their structure is best described as a complex three‐dimensional network, that can be considered to consist of the building units of the binary border phases too, i.e. linear zig‐zag chains of Sn (motif I) like in CaSn, ladders of four‐bonded Sn/Al atoms (II) like in SrAl₂ and trigonal‐bipyramidal clusters [Al₃Sn₂] (III) also present in Ba₃Al₅. Despite the complex structures, some statistically occupied Al/Sn positions and the small disorder of one building unit, the bonding in both structure types can be interpreted using the Zintl concept and Wade's electron counting rules when taking partial Sn‐Sn bonds into account.     

Two Succinato‐bridged Zinc(II) Phenanthroline Complexes: [Zn(phen)L2/2](H2L) and [(phen)2Zn(μ‐L)Zn(phen)2]L � 11H2O with H2L = Succinic Acid

Two mixed ligand Zn^II complexes [Zn(phen)L_2/2](H₂L) ( 1 ) and [(phen)₂Zn(μ‐L)Zn(phen)₂]L � 11H₂O ( 2 ) with H₂L = suc‐cinic acid were prepared and crystallographically characterized. Complex 1 crystallizes in the monoclinic space group C2/c (no. 15) with a = 13.618(1) Å, b = 9.585(1) Å, c = 15.165(1) Å, β = 96.780(6)°, V = 1965.6(3)ų, Z = 4 and complex 2 in the triclinic space group P 1¯ (no. 2) with a = 12.989(2)Å, b = 14.464(2)Å, c = 18.025(3)Å, α = 90.01(1)°, β = 109.69(1)°, γ = 112.32(1)°, V = 2917.4(8) ų, Z = 2. 1 consists of succinic acid molecules and 1D zigzag [Zn(phen)(C₄H₄O₄)_2/2] polymeric chains, in which the tetrahedrally coordinated Zn atoms are bridged by bis ‐ monodentate succinato ligands. Succinic acid molecules play an important role in supramolecular assemblies of the polymeric chains into 2D layers as well as in the stacking of 2D layers. 2 is composed of [(phen)₂Zn(μ‐L)Zn(phen)₂]²⁺ complex cations, succinate anions and hydrogen bonded water molecules. Within the divalent cations, Zn atoms are octahedrally coordinated by four N atoms of two phen ligands and two O atoms of one bis‐chelating succinato ligand. Through the intermolecular π—π stacking interactions, the complex cations form positively charged 2D layers, between which the noncoordinating succinate anions and water molecules are sandwiched.     

Solvothermal Synthesis and Crystal Structure of the New Layered Thioantimonate(III) [Ni(C4H13N3)2]9Sb22S42 · 0.5H2O: Interconnection of the SbS3, SbS4, and SbS5 Primary Building Units Yielding the Very Large Sb30S30 Heteroring

The novel thioantimonate(III) [Ni(dien)₂]₉Sb₂₂S₄₂ · 0.5H₂O was synthesised under solvothermal conditions by reacting elemental Ni, Sb and S in an aqueous solution of diethylenetriamine (dien) (80%). The compound crystallises in the triclinic space group P1¯, a = 8.997(2) Å, b = 15.293(3) Å, c = 34.434(7) Å, α = 85.51(3)°, β = 84.16(3)°, γ = 83.54(3)°, V = 4672.7 (16) ų, Z = 1. The layered [Sb₂₂S₄₂^18—] anion in [Ni(dien)₂]₉Sb₂₂S₄₂ · 0.5H₂O is composed of nine SbS₃ trigonal pyramids, one SbS₄ and one SbS₅ unit. The interconnection of these units by sharing common S atoms yields Sb‐S heterorings of different sizes. Besides the smaller Sb₂S₂ and Sb₃S₃ rings a very large Sb₃₀S₃₀ heteroring is observed. The structure directing effect of the [Ni(dien)₂]²⁺ cations is obvious as they are located above and below the pores of the anion. The nine [Ni(dien)₂]²⁺ cations exhibit different conformations. All Ni²⁺ cations are in an octahedral environment of six N atoms of two dien ligands. The anions and cations are stacked perpendicular to [100] in an alternating fashion.     

Dihalodimethyltin(IV) complexes of 2‐(pyrazol‐1‐ylmethyl)pyridine

Reaction of dichloro‐ and dibromodimethyltin(IV) with 2‐(pyrazol‐1‐ylmethyl)pyridine (PMP) afforded [SnMe₂Cl₂(PMP)] and [SnMe₂Br₂(PMP)] respectively. The new complexes were characterized by elemental analysis and mass spectrometry and by IR, Raman and NMR (¹H, ¹³C) spectroscopies. Structural studies by X‐ray diffraction techniques show that the compounds consist of discrete units with the tin atom octahedrally coordinated to the carbon atoms of the two methyl groups in a trans disposition (Sn? C = 2.097(5), 2.120(5) Å and 2.110(6), 2.121(6) Å in the chloro and in the bromo compounds respectively), two cis halogen atoms (Sn? Cl = 2.4908(16), 2.5447(17) Å; Sn? Br = 2.6875(11), 2.7464(9) Å) and the two donor atoms of the ligand (Sn? N = 2.407(4), 2.471(4) Å and 2.360(5), 2.455(5) Å). In both cases, the Sn? N(pyridine) bond length is markedly longer than the Sn? N(pyrazole) distance. Copyright © 2003 John Wiley & Sons, Ltd.     

Spectral and thermal properties,and the crystal structure of 1,4,5,8-naphthalene-tetracarboxylate dinuclear Ni(II) complex

A novel dinuclear Ni^II complex, [Ni₂(ntc)(H₂O)₁₀]·7(H₂O) (1), with 1,4,5,8-naphthaenetetracarboxylate (ntc) has been synthesized and characterized by X-ray diffraction analysis, IR, UV-vis spectra and thermogravimetric analysis. Complex 1 crystallizes in triclinic system, space group P-1, a = 7.721(3) Å, b = 9.458(3) Å, c = 11.453(4) Å, α = 114.110(6)°, β = 92.184(6)°, γ = 107.472(6)°, V = 715.7(4) ų, Z = 1, final R = 0.048. Each nickel atom is octahedrally coordinated by five aqua ligands and one oxygen atom of the bridging ntc connecting two nickel atoms. The resulting dinuclear Ni^II complex forms a 3D H-bonded network.     

Dichloro(ethylenediamine-<Emphasis Type="Italic">N,N</Emphasis>-di-3-propionato)zinc: Synthesis and crystal structure

Dichloro(ethylenediamine-N,N-di-3-propionato)zinc (I) has been synthesized for the first time by the reaction between acrylic acid and ethylenediamine coordinated with ZnCl₂ in an aqueous medium. Complex I has been characterized by IR, Raman, and ¹H,¹³C NMR spectroscopy, mass spectrometry, and elemental analysis. The X-ray diffraction analysis of complex I has also been performed. Crystals are monoclinic, а = 9.7792(4) Å, b = 9.9805(4) Å, c = 13.1130(5) Å, β = 101.5620(10)°, space group Р2₁/c, Z = 4, V = 1253.88(9) ų, ρ_calc = 1.804 g/cm³. The coordination polyhedra of Zn atoms in complex I are slightly distorted {ZnCl₂O₂} tetrahedra, each of which are built of two chlorine atoms and the carboxyl oxygen atoms of the two propionic groups of two ligand molecules and form a polymeric layer parallel to crystallographic plant (100). Bond lengths are Zn–О 1.970(1) and 1.976(1); Zn–Cl 2.2600(4) and 2.2693(4) Å. The ligand molecule in complex I has a double betaine structure.     

Synthesis,Characterization, and Crystal Structure of Na3B20, determined and refined from X‐ray and Neutron Powder Data

At 1050 ?C boron combines with sodium forming a boride of formerly unknown composition and crystal structure. The investigation of the homogeneous, monophasic, and crystalline powder was performed using X‐ray (23 ?C) and neutron (–271.5 ?C) diffraction methods. The structure solution led to an unusual arrangement of boron atoms, characterized by two different types of polyhedra, a distorted pentagonal bipyramid and a distorted octahedron. The Rietveld refinement of the crystal structure was carried out in the orthorhombic space group Cmmm (X‐ray: a = 18.6945(6) Å, b = 5.7009(2) Å, c = 4.1506(1) Å, V = 442.35(1) ų, Z = 2; R_wp = 0.087, R_p = 0.067).     

New mixed tellurides of nickel and Group 13–14 metals Ni<Subscript>3−δ</Subscript>MTe<Subscript>2</Subscript> (M = Sn,In, Ga)

Three new mixed tellurides of nickel and group 13–14 metals Ni_3−δMTe₂ (M = Sn, In, Ga) were prepared by high-temperature ampoule synthesis and studied by powder X-ray diffraction analysis. The compound Ni_3−δSnTe₂ was also studied by single crystal X-ray diffraction analysis. The structural model of this phase and two analogs was described as consisting of layers with nickel-main group metal bonds confined from the above by tellurium atoms. The van der Waals gap formed through contacts between the tellurium atoms of neighboring layers is partially occupied by nickel atoms. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1879–1881, October, 2007.     

Synthesis,Crystal and Electronic Structure of Layered AMSb Compounds (A = Rb,Cs; M = Zn,Cd)

Synthesis, crystal structure, thermal stability, and electronic band structure of four new metal antimonides AMSb (A = Rb, Cs; M = Zn, Cd) are reported. CsZnSb and RbZnSb crystallize in the hexagonal ZrBeSi structure type, in a P6₃/mmc space group (no. 194, Z = 2) and unit cell dimensions of a = 4.5588(2)/4.5466(4) Å and c = 11.9246(6)/11.0999(10) Å. CsCdSb and RbCdSb crystallize in the tetragonal PbFCl structure type in a P4/nmm space group (no. 129; Z = 2) and unit cell parameters of a = 4.8884(5)/4.8227(3) Å and c = 8.8897(9)/8.5492(7) Å. All four compounds are air- and water-sensitive and are shown through DSC measurements to decompose between 975 K and 1060 K. Analysis of the calculated electronic band structure shows that the Zn-containing antimonides are topologically trivial narrow bandgap semiconductors, whereas Cd-containing compounds exhibit a band inversion along Γ-Z direction.     

Synthesis, structure and physical properties of LnNi(Sn,Sb)3 (Ln=Pr, Nd, Sm, Gd, Tb)

Five new analogues of the β-CeNiSb₃ family have been synthesized and found to be LnNi(Sn,Sb)₃ and isostructural to the previously reported β-CeNiSb₃. LnNi(Sn,Sb)₃ (Ln=Pr, Nd, Sm, Gd, or Tb) crystallizes in the orthorhombic space group, Pbcm, with lattice parameters of a∼12.9 Å, b∼6.1 Å, c∼12.0 Å. The structure consists of layers of nearly square nets of X (X=Sn/Sb) atoms and highly distorted NiX₆ octahedra. Lanthanide atoms are located between layers of X and NiX₆ octahedra. All analogues are metallic and experimental effective magnetic moments are in agreement with the respective Ln³⁺ calculated moments.