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Under solvothermal synthetic condition, lactate derivatives (R)-5-(1- carboxyethoxy)isophthalic acid ((R)-H 3 CIA) and (S)-5-(1-carboxyethoxy)isophthalic acid ((S)–H 3 CIA) assembled with Ca(Ⅱ) and Mn(Ⅱ) ions to obtain enantiomers {[MnCa 0.5 ((R)-CIA)(H 2 O)]·((CH 3) 2 NH 2 CH 3 CO 2) 0.5 (H 2 O)} n (HU21- R ) and {[MnCa 0.5 ((S)-CIA)(H 2 O)]·((CH 3) 2 NH 2 CH 3 CO 2) 0.5 (H 2 O)} n (HU21– S ), respectively. Complexes HU21- R and HU21– S belong to orthorhombic crystal system with chiral space group I 2 1 2 1 2 1. Single crystal X-ray diffraction analysis revealed that all oxygen atoms of synthons (R)-CIA3- and (S)-CIA3- participated in the coordination with metal ions. Thus, semi-rigid (R)-CIA3- and (S)-CIA3- anions become rigid linkers in HU21- R and HU21– S . Fragments of (R)-CIA3- anion are connected by Ca(Ⅱ) ions to build right-handed double helical chains in HU21- R , while the enantiomeric left-handed double helixes are constructed by (S)-CIA3- fragments and Ca(Ⅱ) ions in HU21– S . Additionally, Mn(Ⅱ) centers and CIA3− anions resulted in a rare 4,4,4-connected net with point symbol of (42.62.82) 3 (42.64). Ca(Ⅱ) ions were further filed into Mn-CIA-framework to form a three dimensional structure with one dimensional channel. Moreover, magnetic test indicates that the framework has a canted antiferromagnetic behavior. Enantiomeric lactate derivatives as rigid synthons assembled with Ca(Ⅱ) and Mn(Ⅱ) ions to result in three dimensional helical heterometallic frameworks with one dimensional channels. [Display omitted] • Chiral heterometallic framework. • Double helical chain. • Lactate derivative as rigid synthon. [ABSTRACT FROM AUTHOR]

In this study, single crystals of two new quaternary chalcogenides, CsY 2 M 3 Se 5 (M = Cu and Ag), have been prepared by the molten-flux method at 1273 K. Single-crystal X-ray diffraction studies established that both the compounds crystallize in the space group Cmcm of the orthorhombic crystal system and are isostructural. The title compounds, CsY 2 M 3 Se 5 adopt the RbSm 2 Ag 3 Se 5 structure type. The CsY 2 M 3 Se 5 structure has seven crystallographically independent atomic sites (one Cs, one Y, two Cu/Ag, and three Se sites) that are fully occupied to form a three-dimensional (3D) tunnel-type structure. These valence-precise compounds are built up of the anionic framework of 3 ∞ [Y 2 M 3 Se 5 ]1−, where the Cs+ cations are present in the tunnels as space fillers. The Y atoms in both structures are octahedrally coordinated with six Se atoms, while Cu/Ag (M) atoms form a tetrahedral geometry. These distorted YSe 6 octahedra share corners and edges with neighboring M Se 4 tetrahedra to form 3D anionic networks. An optical absorption study shows the semiconducting nature of the CsY 2 Ag 3 Se 5 in agreement with DFT studies of the title structures. The electronic structure and the theoretical thermoelectric properties of the CsY 2 Cu 3 Se 5 and CsY 2 Ag 3 Se 5 have also been calculated using the DFT method. Single crystals of two new quaternary chalcogenides, CsY 2 M 3 Se 5 (M = Cu and Ag), have been synthesized using the molten-flux method. The optical absorption and DFT studies show the semiconducting nature of the CsY 2 Ag 3 Se 5 compound. [Display omitted] • Single crystals of two new quaternary selenides, CsY 2 M 3 Se 5 (M = Cu and Ag), are synthesized via the reactive-flux method. • Both the compounds are isostructural and form a 3D tunnel-type structure where YSe 6 and M Se 4 act as building blocks. • The Cs atoms reside in the tunnels and form a distorted bicapped trigonal prismatic geometry. • The optical absorption dataset collected for the powdered CsY 2 Ag 3 Se 5 crystals shows a direct bandgap of 1.7(1) eV. • The DFT studies have also confirmed that the CsY 2 M 3 Se 5 are semiconductors. [ABSTRACT FROM AUTHOR]

The novel porous 3D metal-organic framework, [Cd 9 (BTA) 6 (H 2 O) 5 ]·5H 2 O (1) (BTA = benzene-1,3,5-tri- β -acrylate), has been synthesized under hydrothermal condition. The X-ray crystallography revealed that the compound 1 pertains to an orthorhombic crystal system with space group Ibca. The MOF constructed from a centro-symmetric hexagonal wheel-like anionic cluster [Cd 7 (O 2 C) 18 ]4‒ and linked by semi-rigid BTA ligands, leading to an exceptionally complicated topology with point symbol of (42⋅6) 6 (436⋅6105⋅812). Furthermore, it shows excellent thermo-stability in aqueous surroundings. Fluorescence of the compound was evaluated under ultraviolet light irradiation at room temperature. The compound can perform as a highly selective and sensitive luminescence sensor toward metal ions Al3+ and Fe3+ based on the luminous enhancing or quenching phenomenon in aqueous solutions. Thus the new crystalline solid material can be expected to have broad practical applications in detecting, sensing or other related fields. Image 1 • A 3D coordination polymer was constructed with disc-like heptanuclear cadmium carboxylic cluster and extraordinary topology. • The compound showed transcendental thermo-stability and good photoluminescent properties both in solid state and in water mediums. • It can selectively and sensitively detect Al3+ and Fe3+ ions through enhancement or quench luminous intensity. [ABSTRACT FROM AUTHOR]

Abstract Lithium and molybdenum do not form binary phases under thermodynamic control, but they might do under kinetic control upon lithiation of MoS 2. High Lithiation of MoS 2 can either lead to high-lithiated phases [1] or form Li-Mo phases at the lithiation point at which decomposition in Li 2 S and elemental molybdenum can occur. First-principles crystal structure prediction calculations suggest that the LiMo, monoclinic structure, and Li 2 Mo , either orthorhombic or tetragonal structures, can be formed under kinetic control as co-products of the overall process of lithiation of MoS 2. The computed enthalpies of formation of the Li-Mo phases vary considerably if the long-range dispersion interactions are accounted in for the elemental lithium and molybdenum. Graphical abstract High-lithiation of MoS 2 can lead to the formation of kinetically controlled binary phases of Li-Mo. fx1 Highlights • First-principles crystal structure prediction of Li-Mo system in the composition range of x in Li x Mo up to 3. • Two phases are found more stable than others: the monoclinic LiMo and orthorhombic Li 2 Mo phases. • The Li-Mo phases can be co-products of the lithiation reaction of MoS 2. • The Li-Mo formation is favoured by the Mo-Mo interactions, which arrange in planar- and chain-like configurations. [ABSTRACT FROM AUTHOR]

Abstract A novel organic-inorganic hybrid supramolecular Complex (C 2 H 8 N) 4 SiMo 12 O 40 based on Keggin building blocks has been successfully synthesized by solvothermal method. Single-crystal X-ray analysis revealed that it crystallized in orthorhombic system, Pnma space group. The supramolecular crystalline network is formed via intermolecular hydrogen bonds. The target product was characterized by Infrared spectrum, thermogravimetric-differentialthermal, cyclic voltammetry and fluorescent spectrum. Results prove that Complex emits blue fluorescence and has irreversible photochromic properties. Differential thermal-thermogravimetric and cyclic voltammetry shows that Complex has high thermal stability and strong oxidizability. The catalytic performances of Complex were investigated by solid-gas heterogeneous catalysis method. Using solid target product as catalyst, the catalyze degradation of methanol was tested in the temperature range from rt. to 160 °C. When the system flow rate is 5.0 mL min−1, initial concentration of methanol is 5.34 g m−3, reaction temperature is 150 °C, eliminating rate of methanol is 76%, those indicate that Complex has good catalytic activity. Graphical abstract A novel organic-inorganic hybrid supramolecular Complex (C 2 H 8 N) 4 SiMo 12 O 40 based on Keggin building blocks has been successfully synthesized by solvothermal method. It exhibited higher activity for eliminating methanol, when the system flow rate is 5.0 mL min−1, initial concentration of methanol is 5.34 g m−3, reaction temperature is 150 °C, eliminating rate of methanol is 76%, those indicate that Complex has good catalytic activity. fx1 Highlights • One new organic–inorganic compound (C 2 H 8 N) 4 SiMo 12 O 40 has been synthesized by hydrothermal methods, it has high thermal stability, strong oxidation and high catalytic activity, which is rare in the class of catalysts, pointing to potential applications in catalytic oxidation. [ABSTRACT FROM AUTHOR]

Abstract Single crystals of six new alkali lanthanide silicates and germanates were synthesized via the flux growth method. A 2 CeSi 3 O 9 (A = Rb, Cs) and Cs 2 CeGe 3 O 9 crystallize in the Wadeite structure with space group P 6 3 / m and lattice parameters a = 7.1950(2) Å and c = 10.5109(3) Å for the Rb analogue. K 2 CeSi 3 O 9 crystallizes in a previously unobserved monoclinic distortion of the Wadeite structure with space group P 2 1 / n and lattice parameters a = 7.0801(2) Å, b = 10.458(2) Å, c = 12.238(2) Å and β = 90.07(3)°. Finally, Cs 8 Dy 2 Ge 16 O 39 and Cs 8 Dy 2 Ge 16 O 38 F 2 crystallize in two new structure types that are related to each other and to the Wadeite structure. Cs 8 Dy 2 Ge 16 O 39 crystallizes in the monoclinic space group P 2/ c with lattice parameters a = 12.4054(3) Å, b = 7.4310(2) Å, c = 24.5761(6) Å, and β = 90.8849(16)° and Cs 8 Dy 2 Ge 16 O 38 F 2 crystallizes in the orthorhombic space group Pnn 2 with lattice parameters a = 12.3489(4) Å, b = 12.4805(5) Å, and c = 7.3802(3) Å. The synthesis and structure of the six compounds are reported and the crystallochemical reasons for the formation of each structure are discussed. Graphical abstract Alkali rare earth germanates crystallizing in the Wadeite structure type and related structures. fx1 Highlights • Six new alkali rare earth silicates and germinates are grown from molten fluxes. • The compounds crystallize in the Wadeite and new, related structure types. • The crystallochemical reasons for the formation of each structure are discussed. [ABSTRACT FROM AUTHOR]

Two noncentrosymmetric polyphosphates, namely LiCsP 2 O 6 and LiRbP 2 O 6 have been synthesized from the high temperature solution. The structural analysis suggests that both of them crystallize in orthorhombic space group Fdd 2 (No.43), with lattice parameters: a = 18.517(4) Å, b = 19.037(4) Å, c = 13.011(3) Å, and Z  = 32 for LiRbP 2 O 6, while a = 19.009(13) Å, b = 19.402(13) Å, c = 13.180(9) Å, and Z  = 32 for LiCsP 2 O 6 . In the structure, the PO 4 polyhedra are connected through corner-sharing to form 1D infinite (PO 3 ) ∞ chains stretching along the c axis, which are further linked by the LiO 4 polyhedra to construct a 3D framework with two types of tunnels. And the Rb/Cs atoms are filled in or around the periphery of the tunnels to keep the charge equilibrium. The IR spectra verify their structural validity. In addition, other characterizations including the UV−vis−NIR diffuse reflectance spectra, as well as first-principles theoretical studies have been performed on the two compounds. [ABSTRACT FROM AUTHOR]

In the domain Sr 1−x Zr x F 2+2 × studied at 670 °C between the limits 0.333 ≤ x ≤ 0.353, Sr 2 ZrF 8 (x = 0.333) cannot be obtained under our synthesis conditions but a new phase Sr 17 Zr 9 F 70 (x = 0.346) is characterized which clearly shows a great analogy with Ba 2 ZrF 8 and Pb 2 ZrF 8 already described. It presents the same Pnma space group and derives from this basic type by the relation: a = 28.812(10) Å = 3 × a (Ba 2 ZrF 8 ); b = 16.566(6) Å = 3 × b (Ba 2 ZrF 8 ); c = 11.433(4)Å = c (Ba 2 ZrF 8 ). The superlattice along a results from a change in the step of zigzag parallel rows of respectively Sr cations and ZrF 8 polyhedra. The zigzag step is not composition-dependent but more likely depends on the size of the M 2+ cation. The superlattice along b results from an ordered creation of Sr vacancies of multiplicity m = 3 (1 vacancy for 3 Sr) in some Sr raws which changes the Sr/Zr ratio from 2/1 to 1.889/1 (x = 0.346). Then the superstructure along b accommodates the change in stoichiometry in Sr within this phase from Sr 18 Zr 9 F 72 (9 × ”Sr 2 ZrF 8 ”) to Sr 17 Zr 9 F 70 . A second structure of close composition (x = 0.344) shows that the vacant Sr site can be partially occupied in a disordered way by a small proportion of Sr, giving a composition slightly closer to “Sr 2 ZrF 8 ”. Compared to Sr 17 Zr 9 F 70 , the over-stoichiometry mechanism is a solid solution model. For Zr contents comprised between x = 0.346 and 0.353, a series of modulated phases corresponding to various more or less ordered sequences of Sr cations and Sr vacancies along b are characterized by electron diffraction and TEM lattice imaging. They can be interpreted as intermediate between limit phases Sr 17 Zr 9 F 70 (x = 0.346) and Sr 11 Zr 6 F 46 (x = 0.353), of respective multiplicities m = 3 and m = 2 along the same b direction and of modulation vectors q = 1/3b* and q = 1/2b*. Several modulated phases with q modulation vector comprised between 1/3 b* and 1/2 b* can be characterized. [ABSTRACT FROM AUTHOR]

It is found that the known regular structures of MnC 2 O 4 ·2H 2 O (I) do not allow to refine the powder X-ray pattern of (I) properly using the Rietveld method. Implementation of order-disorder scheme [28] via the including of appropriate displacement vector improves the refinement results. Also it is found that in the case of (I) the similar improvement may be achieved using the data on two phases of (I) obtained as result of decomposition MnC 2 O 4 ·3H 2 O single crystal in the mother solution after growth. Thermal decomposition of (I) produce the anhydrous γ-MnC 2 O 4 (II) the structure of which is differ from the known α- and β-modifications of VIIIb transition metal oxalates. The solved ab initio from the powder pattern structure (II) (space group Pmna , a = 7.1333 (1), b = 5.8787 (1), c = 9.0186 (2) Å, V = 378.19 (1) Å 3 , Z = 4 and D x = 2.511 Mg m −3 ) contains seven-coordinated Mn atoms with Mn–O distances of 2.110–2.358 Å, and is not close-packed. Thermal decomposition of (II) in air flows via forming of amorphous MnO, the heating of which up to 723 K is accompanied by oxidation of MnO to Mn 2 O 3 and further recrystallization of the latter. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrid halide perovskite CH 3 NH 3 PbI 3 (MAPbI 3 ) has received rapid progress in power conversion efficiency as promising photovoltaic materials, yet the surface structures and the role of MA cations are not well understood. In this work, we investigated the structural stability and electronic properties of (001) surface of cubic, (001) and (110) surfaces of tetragonal and orthorhombic phases of MAPbI 3 with considering the orientation of MA cations, by density functional theory calculations. We demonstrate that the orientation of MA cations has profound consequences on the structural stability and the electronic properties of the surfaces, in contrast to the bulk phases. Compared with the MA-I terminated surfaces, the Pb-I 2 terminated ones generally have smaller band gaps and the advantage to enable the photo-excited holes to transfer to the hole-transport materials in both tetragonal and orthorhombic phases. Overall, we suggest that the films with Pb-I 2 terminated surfaces would prevail in high performance solar energy absorbers. [ABSTRACT FROM AUTHOR]

Herein, the high-pressure/high-temperature synthesis (11 GPa, 650 °C) of Tb 3 B 10 O 17 (OH) 5 in a modified Walker-type multianvil device is presented. The structure of this rare-earth borate was determined by single-crystal X-ray diffraction methods and was found to crystallize orthorhombically in the space group Pmn 2 1 (no. 31) with the unit cell parameters a = 16.2527(4), b = 4.4373(1), and c = 8.8174(2) Å. The new compound was further characterized using infrared spectroscopy, energy-dispersive X-ray spectroscopy, second harmonic generation (SHG) measurements, and temperature-dependent X-ray powder diffraction. Tb 3 B 10 O 17 (OH) 5 decomposes to β -Tb(BO 2) 3 at temperatures higher than 460 °C. With increasing temperatures, the formation of μ -TbBO 3 was observed, which transforms to π -TbBO 3 upon cooling. The hydroxyl-containing terbium borate Tb 3 B 10 O 17 (OH) 5 was synthesized under high-pressure conditions in a Walker-type multianvil device at 11 GPa and 650 °C. The new compound was found to crystallize in the orthorhombic space group Pmn 2 1 (no. 31) with the unit cell parameters a = 16.2527(4), b = 4.4373(1), c = 8.8174(2) Å, and two formula units per cell by single-crystal diffraction methods. Tb 3 B 10 O 17 (OH) 5 was further characterized using infrared spectroscopy, energy-dispersive X-ray spectroscopy, second harmonic generation (SHG) measurements, and temperature-dependent X-ray powder diffraction. Tb 3 B 10 O 17 (OH) 5 decomposes to β -Tb(BO 2) 3 at temperatures higher than 460 °C. With increasing temperature, the formation of μ -TbBO 3 was observed, which transforms to π -TbBO 3 upon cooling. [Display omitted] • Tb 3 B 10 O 17 (OH) 5 was synthesized at 11 GPa and 650 °C in a Walker-type multianvil device. • Tb 3 B 10 O 17 (OH) 5 crystallizes non-centrosymmetrically in the orthorhombic crystal system. • Tb 3 B 10 O 17 (OH) 5 is stable up to 460 °C. • Above 460 °C, the formation of β -Tb(BO 2) 3 is observed, which further decomposes to μ -TbBO 3. • Upon cooling, μ -TbBO 3 transforms to π -TbBO 3. [ABSTRACT FROM AUTHOR]

Two new metal chalcogenides, Ba 5 Pb 2 Sn 3 S 13 (BPSS) and Ba 6 PbSn 3 Se 13 (BPSSe), were successfully synthesized in vacuum–sealed silica tubes for the first time. Both of them are isostructural and crystallize in the Pnma space group of orthorhombic system. Their three-dimensional (3D) framework structures are composed of 2D layers formed by the interconnection of [(Pb/Ba)Q n ] ( n = 6 and 7) polyhedra and isolated SnQ 4 tetrahedra and charge–balanced Ba atoms filled into the interlayers. Note that the Q8 atoms are only surrounded by two Pb/Ba and four Ba atoms to form the distorted octahedra without the covalent Sn-Q bonds in their structures. Measured results of diffuse reflection and Raman spectra show that title compounds possess the wide transmission ranges from 0.5 to 20 µm. Electronic structures and linear optical properties were also systematically investigated by the first–principle calculation, and calculated results indicate that title compounds possess the large birefringences about 0.123 and 0.135 for BPSS and BPSSe at 1 µm, respectively, which indicate that they may be expected as potential IR birefringent materials. [ABSTRACT FROM AUTHOR]

The ambient temperature structure of Cu 4 SnS 4 has been revisited and the recently reported low temperature structure has been confirmed from single-crystal X-ray diffraction data. A structural phase transition from a large monoclinic unit cell at low temperature to a smaller orthorhombic unit cell at high temperature has been observed. The room temperature phase exhibited disorder in the two copper sites, which is a different finding from earlier reports. The low temperature monoclinic form crystallizes in P 2 1 / c space group, which is isostructural with Cu 4 GeS 4 . The phase transition has also been studied with variable temperature powder X-ray diffraction and 119 Sn Mössbauer spectroscopy. The Seebeck coefficients and electrical resistivity of polycrystalline Cu 4 SnS 4 are reported from 16 to 400 K on hot pressed pellets. Thermal conductivity measurements at high temperatures, 350 – 750 K exhibited very low thermal conductivities in the range 0.28 – 0.35 W K –1 m –1 . In all the transport measurements the phase transition has been observed at around 232 K. Resistivity decreases, while Seebeck coefficient increases after the phase transition during warming up from low to high temperatures. This change in resistivity has been correlated with the results of first-principles electronic band structure calculations using highly-accurate screened-exchange local density approximation. It was found that both the low hole effective mass of 0.63 m e for the Γ→Y crystallographic direction and small band gap, 0.49 eV, are likely to contribute to the observed higher conductivity of the orthorhombic phase. Cu 4 SnS 4 is also electrochemically active and shows reversible reaction with lithium between 1.7 and 3.5 volts. [ABSTRACT FROM AUTHOR]

The equiatomic intermetallic compounds RE IrMg ( RE = Y, La-Nd, Sm, Gd-Tm) and RE RhMg ( RE = Y, Sm, Gd-Tm) were synthesized from the elements in sealed niobium ampoules in a high-frequency furnace and characterized based on X-ray powder data. LaIrMg and CeIrMg crystallize with the orthorhombic LaNiAl type structure ( Pnma ), while all other compounds adopt the TiNiSi type. The structures of YRhMg, GdRh 1.190(4) Mg 0.810(4) , DyRh 1.126(5) Mg 0.874(5) , LaIrMg, NdIr 1.033(2) Mg 0.967(2) and ErIr 1.059(3) Mg 0.941(3) were refined from single-crystal X-ray diffractometer data. The striking structural motifs of these phases are tricapped trigonal prisms around the transition metal atoms formed by RE and Mg. The two structure types differ in the connectivity pattern of the trigonal prisms. The rhodium (iridium) atoms build up three-dimensional [RhMg] and [IrMg] networks in which cavities are filled by the rare earth atoms. Temperature dependent magnetic susceptibility measurements on X-ray pure samples of NdIrMg, SmRhMg, GdRhMg, TbRhMg and DyRhMg show Curie-Weiss paramagnetism of the trivalent rare earth ions and magnetic ordering at low temperatures: T C = 9.5 K for NdIrMg and Néel temperatures of 10.0, 16.7, 10.6 and 11.3 K for SmRhMg, GdRhMg, TbRhMg and DyRhMg. TbRhMg and DyRhMg exhibit field-induced spin reorientations (metamagnetism). [ABSTRACT FROM AUTHOR]

Li 3 K 3 Y 7 (BO 3 ) 9 was prepared by high-temperature solid state synthesis at 900 °C in a platinum crucible from lithium carbonate, potassium carbonate, boric acid, and yttrium(III) oxide. The compound crystallizes in the orthorhombic space group Pca 2 1 (no. 29) ( Z = 4). The structure was refined from single-crystal X-ray diffraction data: a = 20.743(8), b = 6.387(4), c = 17.474(4) Å, V = 2315.2(2) Å 3 , R 1 = 0.0473, and wR 2 = 0.0637 for all data. The crystal structure of Li 3 K 3 Y 7 (BO 3 ) 9 consists of isolated BO 3 groups forming [Li 3 B 4 O 21 ] units in combination with LiO 6 octahedra in the ac plane, which are interconnected to each other by additional planar BO 3 groups. The Y 3+ and K + cations are arranged in layers along the a -axis. [ABSTRACT FROM AUTHOR]

The phase equilibria in the ½Nd 2 O 3 –SrO–CoO system were systematically studied at 1373 K in air. The intermediate phases formed in the ½Nd 2 O 3 –SrO–CoO system at 1373 K in air are: Nd 1- x Sr x CoO 3-δ (0.0≤ x ≤0.5 with orthorhombic structure, sp. gr. Pbnm and 0.6≤ x ≤0.95 whose structure was detected as cubic according to XRD sp. gr. Pm 3 m , but shown to be tetragonal by TEM due to the oxygen vacancy ordering), Nd 2- y Sr y CoO 4-δ (0.6≤ y ≤1.1 with tetragonal K 2 NiF 4 -type structure, sp. gr. I 4 /mmm ) and Nd 2- z Sr z O 3 (0.0≤ z ≤0.15 with hexagonal structure, sp. gr. P- 3 m 1). The unit cell parameters for the single phase samples were refined by the Rietveld analysis. The changes of oxygen content in Nd 1- x Sr x CoO 3-δ (0.6≤ x ≤0.95) and Ruddlesden-Popper oxide Nd 2- y Sr y CoO 4-δ were examined by TGA. All were found to be oxygen deficient phases. High-temperature dilatometry allows calculating the thermal expansion coefficient and evaluating the chemical expansion coefficient at high temperature. The projection of isothermal-isobaric phase diagram for the Nd–Sr–Co–O system at 1373 K in air to the compositional triangle of metallic components has been constructed. The phase equilibria in the studied Nd–Sr–Co–O system were compared to La–Sr–Co–O and Nd–M–Co–O (M=Ca and Ba). [ABSTRACT FROM AUTHOR]

Two novel solid solution series, Ba 2- x La x InIrO 6 ( x =0–1.0) and BaLaIn 1- y Ca y IrO 6 ( y =0–1.0), were prepared and several changes in structure, moment and charge transport were observed. The Ba 2- x La x InIrO 6 series exhibits a transition from a 6M polytype to an orthorhombic perovskite structure with increased La content whereas the BaLaIn 1- y Ca y IrO 6 series transitioned from a disordered, orthorhombic perovskite to an ordered, cubic perovskite with increased Ca content. Seebeck measurements for both systems showed that Ir(IV)-rich compounds tended to have a n-type conduction mechanism while Ir(V)-rich compounds tended to be p-type. Both systems were found to be semiconducting and the magnitude of the resistivity is dependent on crystal structure and Ir environment. Magnetic measurements show that the μ eff values for both systems are significantly less than predicted for Ir(IV) (1.73 μ B ) and greater than predicted for Ir(V) (0 μ B ). These results are compared to other iridate compound families. [ABSTRACT FROM AUTHOR]

Magnetic structure of CaFe 5 O 7 ferrite has been studied jointly from neutron powder diffraction data and spectroscopic Mössbauer measurements in the thermal range from 5 to 500 K. This coupled work highlights three distinct magnetic domains around two specific temperatures: T M =125 K and T N =360 K. The latter corroborates the structural monoclinic-orthorhombic transition previously reported by transmission electron microscopy techniques and X-ray thermodiffractometry. Complementary heat capacity measurements have confirmed this first order transition with a sharp peak at 360 K. Interestingly, this large study has revealed a second magnetic transition associated to a spin rotation at 125 K similar to this one reported by Morin in α-Fe 2 O 3 hematite at T M =260 K. [ABSTRACT FROM AUTHOR]

A new phase in the Rh-Cd binary system - Rh 2 Cd 5 has been identified and characterized by single crystal X-ray diffraction and Energy dispersive X-ray analysis. The stoichiometric compound Rh 2 Cd 5 crystallizes with a unit cell containing 14 atoms, in the orthorhombic space group Pbam (55). The crystal structure of Rh 2 Cd 5 can be described as a defect form of the In 3 Pd 5 structure with ordered vacancies, formed of two 2D atomic layers with the stacking sequence: ABAB. The A type layers consist of (3.6.3.6)-Kagomé nets of Cd atoms while the B type layers consist of (3 5 ) (3 7 )- nets of both Cd and Rh atoms. The stability of this line phase is investigated by first principle electronic structure calculations on the model of ordered Rh 2 Cd 5 . [ABSTRACT FROM AUTHOR]

The organic-inorganic metal halide perovskite materials have remarkable semiconductor and light absorption characteristics. It shows excellent application prospects in the fields of optoelectronics and temperature sensors. In this work, zero-dimensional lead-free (C 6 H 14 N) 3 Bi 2 I 9 ·H 2 O single crystals were synthesized by conventional solvothermal reaction. The crystal structure was analyzed using single crystal X-ray diffraction (SXRD). (C 6 H 14 N) 3 Bi 2 I 9 ·H 2 O was crystallized in the orthorhombic crystal system with the space group Pmn2 1. The material is stable for long-term storage under ambient conditions and shows a reversible thermochromic phenomenon. Through ultraviolet–visible–near-infrared (UV–vis–NIR) absorption analysis, the band gap of (C 6 H 14 N) 3 Bi 2 I 9 ·H 2 O at room temperature is found to be 2.12 ​eV and it gradually decreases as the temperature increases. This indicates that the thermochromism is probably caused by charge transfer. The response of material to optical signals was also studied and the maximum value of the responsivity (R) and external quantum efficiency (EQE) at 275 ​nm could reach 11 ​mA/W and 2.4%, respectively. It suggests that the material has a potential for applications in photovoltaic devices. The quasi zero-dimensional lead-free single crystals (C 6 H 14 N) 3 Bi 2 I 9 ·H 2 O were synthesized by solvothermal reaction, which was crystallized in the orthorhombic crystal system with the space group Pmn2 1. It shows a reversible thermochromic phenomenon which may be caused by electrons excitation and charge transfer of bismuth (Bi) element with the increase of temperature. [Display omitted] • The new lead-free organic-inorganic hybrid single crystal (C 6 H 14 N) 3 Bi 2 I 9 ·H 2 O was synthesized and the crystal structure were analyzed. • (C 6 H 14 N) 3 Bi 2 I 9 ·H 2 O crystal has a typical zero-dimensional structure which has ideal structural flexibility. • The (C 6 H 14 N) 3 Bi 2 I 9 ·H 2 O has outstanding thermal stability, reversible thermochromic properties and good photoelectric properties. • As the temperature increases, the hyperchromic effect was observed and the band gap decreases significantly. [ABSTRACT FROM AUTHOR]

The band structure of three-dimensional and two-dimensional tin monosulfide was calculated by the density functional method in LDA and LDA+ U approximations. Group-theoretical analysis of the electronic band structure of SnS crystallized in the orthorhombic structure with space group D 2 h 16 – Pcmn is carried out, the symmetry of wave functions of the valence band and the bottom of the conduction band is found. The selection rules for direct and indirect optical transitions at different incident light polarization are determined. The group-theoretical analysis of energy states of the three-dimensional and two-dimensional SnS structures explains the formation of the band structure including the Davydov splitting. The calculated total density of states is compared with the known experimental XPS and UPS spectra, providing the assignment of their main features. [ABSTRACT FROM AUTHOR]

Li 4 MgOsO 6 was synthesized by two different solid-state reaction procedures. The crystal structures were determined by X-ray powder diffraction technique and it was revealed that Li 4 MgOsO 6 crystallizes in two different crystal symmetries in ordered rock salt structure type, namely monoclinic C2/m and orthorhombic Fddd . The unit cell constants for the monoclinic system are a =5.1074(4) Å, b= 8.8182(4) Å, c= 5.0902(2) Å, and β =109.845 ( 4)° and those of the orthorhombic structure are a =5.8485(1) Å, b =8.3821(1) Å, and c =17.6212(3) Å. In both systems, Os 6+ ions reside exclusively in a specific crystallographic position while Li + and Mg 2+ ions exhibit mix occupancy. The temperature dependent magnetic susceptibility data for both S=1 osmate systems do not support the occurrence of any magnetic transition down to 2 K. The Curie–Weiss fit to the paramagnetic regime of the magnetic susceptibility data reveal highly negative θ value (−114.81 K and −121.87 K for C2/m and for Fddd systems , respectively ) , which are indicative of predominant antiferromagnetic (AFM) interactions in both systems. The experimental effective magnetic moment ( μ eff ) value for the monoclinic phase is 2.13 μB and that of the orthorhombic system is 2.34 μB . Due to the rather strong AFM interactions and lack of magnetic transition down to 2 K, both of these novel osmates are placed in the class of highly frustrated magnets. Low temperature magnetic susceptibility (below 2 K) and dynamic magnetic properties studies (μsr studies) are in order to better understand the magnetic ground states of these two polymorphs of Li 4 MgOsO 6 . [ABSTRACT FROM AUTHOR]

New fluorite-related quaternary rare earth oxides Pr 2 YRuO 7 and La 2 TbRuO 7 have been prepared. They crystallize in an orthorhombic superstructure of cubic fluorite with space group Cmcm . Through magnetic susceptibility and specific heat measurements, Pr 2 YRuO 7 shows an antiferromagnetic transition at 27 K, which is considerably lowered compared with that for Pr 3 RuO 7 . Analysis of the magnetic specific heat indicates that the magnetic behavior observed at 27 K for Pr 2 YRuO 7 is predominantly due to the magnetic interactions between Ru ions, and that the interactions between the Pr 3+ and Ru 5+ ions are also important. La 2 TbRuO 7 shows magnetic ordering at 9.0 K, which is ascribed to the magnetic ordering between Ru 5+ ions from the analysis of the magnetic specific heat data. [ABSTRACT FROM AUTHOR]

The high pressure behaviors of the two perovskite structures (hexagonal 6H-SrIrO 3 and orthorhombic 3C-SrIrO 3 ) have been studied in diamond anvil cells to 43 and 60 GPa, respectively, using synchrotron powder X-ray diffraction. 6H-SrIrO 3 was first synthesized at ambient pressure and subsequently transformed into 3C-SrIrO 3 in a large volume press at 8.8 GPa and 1000 °C. Both polymorphs were found to retain the initial symmetry up to the highest pressures measured, but in the case of 6H-SrIrO 3 , two anomalies were identified: a change in the axial compressibilities at 24 GPa and a change in both the axial and volume compressibilities at 32 GPa. Fitting a 3rd order Birch-Murnaghan equation of state to the obtained P-V data yielded bulk moduli of K 0 =151.5(12) GPa (fitted range 0< P <30 GPa) for 6H-SrIrO 3 and K 0 =187.1(9) GPa for 3C - SrIrO 3 . Analysis of the structural parameters for 6H-SrIrO 3 aided by F-f plots suggests the anomalies are caused by changes in the compression mechanism. Comparison of the two polymorphs reveals that 6H-SrIrO 3 becomes less compressible than 3C-SrIrO 3 above 32 GPa as a result of the mechanistic change, and a crossing of their P-V curves is avoided. For 3C-SrIrO 3 , analysis of the octahedral tilt angles shows that these increase monotonically from the ambient value of 7.23(6) to 23.0(2)° at 60 GPa suggesting that a transition to a post-perovskite is approached. [ABSTRACT FROM AUTHOR]

The structures of some A UO 4 ( A =Ca, Sr, or Ba) oxides have been determined using a combination of neutron and synchrotron X-ray diffraction, supported by X-ray absorption spectroscopic measurements at the U L 3 -edge. The smaller Ca cation favours a rhombohedral A UO 4 structure with 8-coordinate UO 8 moieties whilst an orthorhombic structure based on UO 6 groups is found for BaUO 4 . Both the rhombohedral and orthorhombic structures can be stabilised for SrUO 4 . The structural studies suggest that the bonding requirements of the A site cation play a significant role in determining which structure is favoured. In the rhombohedral structure, Bond Valence Sums demonstrate the A site is invariably overbonded, which, in the case of rhombohedral α-SrUO 4 , is compensated for by the formation of vacancies in the oxygen sub-lattice. The uranium cation, with its flexible oxidation state, is able to accommodate this by inducing vacancies along its equatorial coordination site as demonstrated by neutron powder diffraction. [ABSTRACT FROM AUTHOR]

This article reports two new Hf-rich intermetallics synthesized using Sn flux: Hf 3 Fe 4 Sn 4 and Hf 9 Fe 4− x Sn 10+ x . Hf 3 Fe 4 Sn 4 adopts an ordered variant the Hf 3 Cu 8 structure type in orthorhombic space group Pnma with unit cell edges of a =8.1143(5) Å, b =8.8466(5) Å, and c =10.6069(6) Å. Hf 9 Fe 4− x Sn 10+ x , on the other hand, adopts a new structure type in Cmc 2 1 with unit cell edges of a =5.6458(3) Å, b =35.796(2) Å, and c =8.88725(9) Å for x =0. It exhibits a small amount of phase width in which Sn substitutes on one of the Fe sites. Both structures are fully three-dimensional and are characterized by pseudo one- and two-dimensional networks of Fe–Fe homoatomic bonding. Hf 9 Fe 4− x Sn 10+ x exhibits antiferromagnetic order at T N =46(2) K and its electrical transport behavior indicates that it is a normal metal with phonon-dictated resistivity. Hf 3 Fe 4 Sn 4 is also an antiferromagnet with a rather high ordering temperature of T N =373(5) K. Single crystal resistivity measurements indicate that Hf 3 Fe 4 Sn 4 behaves as a Fermi liquid at low temperatures, indicating strong electron correlation. [ABSTRACT FROM AUTHOR]

Experimental measurements clearly reveal the presence of bulk superconductivity in the CsPb x Bi 4− x Te 6 (0.3≤ x ≤1.0) materials, i.e. the first member of the thermoelectric series of Cs[Pb m Bi 3 Te 5+ m ], these materials have the layered orthorhombic structure containing infinite anionic [PbBi 3 Te 6 ] − slabs separated with Cs + cations. Temperature dependences of electrical resistivity, magnetic susceptibility, and specific heat have consistently demonstrated that the superconducting transition in Cs 0.96 Pb 0.25 Bi 3.75 Te 6.04 occurs at T c =3.1 K, with a superconducting volume fraction close to 100% at 1.8 K. Structural study using aberration-corrected STEM/TEM reveals a rich variety of microstructural phenomena in correlation with the Pb-ordering and chemical inhomogeneity. The superconducting material Cs 0.96 Pb 0.25 Bi 3.75 Te 6.04 with the highest T c shows a clear ordered structure with a modulation wave vector of q ≈ a */2+ c */1.35 on the a – c plane. Our study evidently demonstrates that superconductivity deriving upon doping of narrow-gap semiconductor is a viable approach for exploration of novel superconductors. [ABSTRACT FROM AUTHOR]

Black, metallic luster, platelet single crystals of Ba 26 B 12 Si 5 N 27 were grown on a BN crucible wall by slowly cooling from 900 °C to 27 °C. X-ray diffraction analysis revealed that Ba 26 B 12 Si 5 N 27 crystallizes in an orthorhombic cell ( a =17.6942(4) Å, b =34.1437(6) Å, c =10.0410(2) Å; space group Fdd 2). Isolated nitridoborate anionic groups [BN 2 ] 3– , dumbbell-type Zintl polyanions [Si 2 ] 2.8– , and nitride anions N 3– are included in the structure. The structural formula is represented as (Ba 2+ ) 26 {[BN 2 ] 3– } 12 [{[Si 2 ] 2.8– } 1.25 (N 3– ) 2×0.75 ] 2 . The [Si 2 ] 2.8– dumbbell with a Si–Si length of 2.177(5) Å has a bond order of 2.6, which is close to the triple bond of Si. [ABSTRACT FROM AUTHOR]

The thermal evolution of the crystal structure of the prototypical orthorhombic perovskite LaFeO 3 has been studied in detail by powder neutron diffraction in the temperature range 25< T <1285 K. A conventional bond length/bond angle analysis, combined with an analysis in terms of symmetry-adapted modes, allows key aspects of the thermal behavior to be understood. In particular, the largest-amplitude symmetry modes ( viz. in-phase and out-of-phase octahedral tilts, and A-site cation displacements) are shown to display relatively ‘normal’ behavior, increasing with decreasing temperature, which contrasts with the anomalous behavior previously shown by the derivative Bi 0.5 La 0.5 FeO 3 . However, an unexpected behavior is seen in the nature of the intra -octahedral distortion, which is used to rationalize the unique occurrence of a temperature dependent crossover of the a and c unit cell metrics in this compound. [ABSTRACT FROM AUTHOR]

The high-pressure behavior of the orthorhombic cotunnite type ZrO 2 is explored using an ab initio constant pressure technique. For the first time, a novel hexagonal phase (Ni 2 In type) within P6 3 /mmc symmetry is predicted through the simulation. The Ni 2 In type crystal is the densest high-pressure phase of ZrO 2 proposed so far and has not been observed in other metal dioxides at high pressure before. The phase transformation is accompanied by a small volume drop and likely to occur around 380 GPa in experiment. [ABSTRACT FROM AUTHOR]

Magnetic properties, magnetocaloric effect and heat capacity of the YNi 4 Si-type SmNi 4 Si compound have been investigated. SmNi 4 Si exhibits ferromagnetic transition at 17 K. Below ~9 K, the magnetic isotherms of SmNi 4 Si show metamagnetic-like behavior with critical field of 20 kOe at 5 K. Heat capacity measurements of SmNi 4 Si show the electronic heat capacity coefficient γ =94 mJ/(mol K 2 ), phonon coefficient β =0.35 mJ/(mol K 4 ) and Debye temperature T D =310 K. The magnetocaloric effect of SmNi 4 Si is calculated in terms of isothermal magnetic entropy change which is obtained by the isothermal magnetization (Δ S m magn ) and heat capacity measurements (Δ S m heat ). Both Δ S m magn and Δ S m heat reach a maximum of –1.0 J/kg K at 17 K for a field change of 50 kOe and they show positive values for a field change of 20 kOe at ~9 K. Below 15 K, SmNi 4 Si shows large magnetic hysteresis with considerable remanence. At 5 K it exhibits giant coercive field of 58 kOe in an applied field of 90 kOe. [ABSTRACT FROM AUTHOR]

High-pressure synthesis experiments in a piston–cylinder apparatus at 1.5 GPa/3.0 GPa and 1000 °C resulted in the formation of single-crystals of Sr 2 Ga 2 O 5 and Sr 5 Ga 6 O 14 , respectively. The structures of both compounds have been solved from single-crystal diffraction data sets using direct methods. The first compound is orthorhombic with space group type Pbca ( a =10.0021(4) Å, b =9.601(4) Å, c =10.6700(4) Å, V =1024.6(4) Å 3 , M r =394.68 u, Z =8, D x =5.12 g/cm 3 ) and belongs to the group of single layer gallates. Individual sheets are parallel to (0 0 1) and can be built from the condensation of unbranched vierer single chains running along [0 1 0]. The layers are characterized by the presence of four- and strongly elliptical eight-membered rings of corner connected tetrahedra in UUDD and UUUUDDDD conformation. Strontium atoms are sandwiched between the tetrahedral layers for charge compensation and are coordinated by six and seven oxygen ligands, respectively. Sr 2 Ga 2 O 5 is isotypic with several other double sulfides and selenides. To the best of our knowledge, it is the first example of an oxide with this structure type. From a structural point of view, Sr 5 Ga 6 O 14 is a phyllogallate as well. The crystal structure adopts the monoclinic space group P 2 1 /c ( a =8.1426(3) Å, b =8.1803(3) Å, c =10.8755(4) Å, β= 91.970(4)° V =723.98(5) Å 3 , M r =1080.42 u, Z =2, D x =4.96 g/cm 3 ). Individual sheets extend along (0 0 1). Basic building units are unbranched dreier single chains parallel to [1 0 0]. The layers contain tertiary (Q 3 ) und quaternary (Q 4 ) connected [GaO 4 ]-tetrahedra in the ratio 2:1 resulting in a Ga:O ratio of 3:7 and the formation of exclusively five-membered rings. Linkage between adjacent tetrahedral sheets is provided by three symmetrically independent strontium ions which are surrounded by six to eight oxygen atoms. The layers in Sr 5 Ga 6 O 14 are similar to those observed in the melilite structure-type. Crystallochemical relationships between the present phases and other known compounds are discussed in detail. [ABSTRACT FROM AUTHOR]

We present a systematic study of the structure and lattice dynamics at room temperature, and the phonon behavior at low temperatures in orthorhombic Gd 1− x Y x MnO 3 manganites, with 0≤ x ≤0.4. Powder x-ray diffraction and Raman scattering at ambient conditions reveal that the Jahn–Teller distortion is composition-independent, while the Mn–O1–Mn bond angle increases by about 0.5° from x =0 to x =0.4. The spin–phonon coupling was ascertained from the relation between the renormalized wavenumber of the in-plane O2 stretching mode, associated with the spin–spin correlation function. The balance between competitive magnetic interactions is discussed based on the temperature dependence of the phonon frequency renormalization. [ABSTRACT FROM AUTHOR]

Single crystals of the new quaternary compound In 4 Ti 1.5 Mo 0.5 Mo 14 O 26 were obtained by solid state reaction. The crystal structure was determined by single-crystal X-ray diffraction. In 4 Ti 1.5 Mo 0.5 Mo 14 O 26 crystallizes in the orthorhombic space group Pbca with unit-cell parameters a =9.4432(14) Å, b =11.4828(12) Å, c =20.299(4) Å and Z =4. Full-matrix least-squares refinement on F 2 using 3807 independent reflections for 219 refinable parameters resulted in R 1 =0.0259 and w R 2 =0.0591. The crystal structure contains in addition to Mo 14 clusters the first examples of mono- and bi-capped trioctahedral Mo 14 i.e. Mo 15 and Mo 16 clusters. The oxygen framework derives from a stacking along the a direction of close-packed layers with sequence (…ABAC…). The Mo–Mo distances range between 2.6938(5) and 2.8420(6) Å and the Mo–O distances between 1.879(5) and 2.250(3) Å, as usually observed in molybdenum oxide clusters. The indium atoms form In 4 6+ bent chains with In–In distances of 2.6682(5) and 2.6622(8) Å and the Ti atoms are in highly distorted octahedral sites of oxygen atoms with Ti–O distances ranging between 1.865(4) and 2.161(4) Å. Magnetic susceptibility measurements confirm the presence of Ti 4+ cations and the absence of localized moments on the Mo network. Electrical resistivity measurements on a single crystal of In 4 Ti 1.5 Mo 0.5 Mo 14 O 26 show a semimetallic behavior. [ABSTRACT FROM AUTHOR]

The crystal structures of seven samples of orthorhombic ( Pnma ) Ln 2 TiO 5 compounds with Ln =La, Pr, Nd, Sm, Gd, Tb and Dy were refined by Rietveld analysis of synchrotron X-ray powder diffraction (S-XRD) data. With increasing size of the lanthanide cation, the lattice parameters increase systematically: c by only ~1.5% whereas both a and b by ~6% from Dy 2 TiO 5 to La 2 TiO 5 . The mean Ti–O bond length only increases by ~1% with increasing radius of the Ln cation from Gd to La, primarily due to expansion of the pair of Ti–O 3 bonds to opposite corners of the Ti–O 5 square based pyramid polyhedra. For Dy 2 TiO 5 and Tb 2 TiO 5 , a significant variation in Ti–O 1 and Ti–O 4 bond lengths results in an increased deformation of the Ti–O 5 base. The particular configuration consists of large rhombic shaped tunnels and smaller triangular tunnels along the b axis, which have implications for defect formation and migration caused by radiation damage or the ionic conductivity. [ABSTRACT FROM AUTHOR]

Four new Zintl phases, Ca 21 Zn 4 As 18 , Ca 21 Zn 4 Sb 18 , Eu 21 Zn 4 As 18 and Eu 21 Zn 4 Sb 18 have been synthesized by metal flux reactions. Their structures have been established from single-crystal X-ray diffraction. Despite the similar chemical makeup and the identical formulae, the structures of the four compounds are not the same—Ca 21 Zn 4 As 18 , Ca 21 Zn 4 Sb 18 and Eu 21 Zn 4 As 18 crystallize in the monoclinic space group C 2 /m (No. 12, Z =4) with the β -Ca 21 Mn 4 Sb 18 structure type, while Eu 21 Zn 4 Sb 18 adopts the Ba 21 Cd 4 Sb 18 structure type with the orthorhombic space group Cmce (No. 64, Z =8). Both structures are based on ZnAs 4 or ZnSb 4 tetrahedra, linked in slightly different ways, and Ca 2+ and Eu 2+ cations that fill the space between them. The structural relationships between the title compounds and other known ternary phases with intricate structures are discussed. Electrical resistivity measurement on single-crystalline Eu 21 Zn 4 Sb 18 suggests an intrinsic semiconductor behavior with a band gap of ca. 0.2 eV. The temperature dependent DC magnetization measurement on the same material indicates Curie–Weiss paramagnetism in the high-temperature regime, and a spontaneous antiferromagnetic ordering below 8 K. The calculated effective moments of Eu confirm the divalent Eu 2+ ground state, as expected from the Zintl–Klemm concept. [ABSTRACT FROM AUTHOR]

Structural, magnetic, and electric properties have been investigated in polycrystalline Bi 2 (Fe 1− x Al x ) 4 O 9 (0≤ x ≤0.25) ceramics synthesized by a modified Pechini method. Structural analysis reveals that Al 3+ doped Bi 2 Fe 4 O 9 crystallizes in orthorhombic structure with Pbnm space group. Surface morphology of the end products is examined by scanning electron microscopy and the grain size has a tendency to decrease with increase in Al 3+ doping level. Compared with pure Bi 2 Fe 4 O 9 , room temperature coexistent multiferroic-like behavior is observed in Al 3+ doped Bi 2 Fe 4 O 9 . By analyzing magnetic properties, the Néel temperature monotonously shifts to low temperatures from ~260 K ( x =0) to ~35 K ( x =0.25). Moreover, the spin dynamic measured by the shift in ac magnetic susceptibility as a function of frequency provides a possibility of spin-glass-like behavior, which is further confirmed by fitting the critical slowing down power law and memory effect. [ABSTRACT FROM AUTHOR]

Three new one-dimensional energetic coordination polymers (ECPs) were prepared by solvothermal method and liquid diffusion method, namely, [Mn(BODDTO)(H 2 O) 4 ] n (1), [Zn(BODDTO)(H 2 O) 4 ] n (2) and [Pb(BODDTO)(H 2 O) 4 ] n (3) (H 2 BODDTO ​= ​5,5'-([3,3′-bi(1,2,4-oxadiazole)]-5,5′-diyl)bis(1H-tetrazol-1-ol)). Compounds 1 and 2 possess the same crystal structures, crystallizing in the triclinic space group P-1 with a calculated density of 1.970 ​g ​cm−3 for 1 and 2.047 ​g ​cm−3 for 2. Meanwhile, Compound 3 pertains to the P2 1 2 1 2 1 space group of the orthorhombic crystal system with a density of 2.618 ​g ​cm−3. The thermal behaviors were studied by employing a Thermogravimetry instrument, the results show that the compounds have good thermal stability with the decomposition temperatures above 520 ​K. The studies of mechanical sensitivity and detonation performance reveal that these complexes are both safe and have high energy. Furthermore, the ability to catalyze the thermal decomposition of ammonium perchlorate (AP) by compounds 1 – 3 was studied through a differential thermal analysis instrument. The high-temperature decomposition peak temperature of AP is reduced by 94.8 ​K at most and the activation energy is also decreased. It is disclosed that three compounds can be potentially used as high-energy AP catalysts. The single-crystal structures of three energetic coordination polymers (ECPs) were determined using single crystal X-ray diffraction. These ECPs possess good thermal stability by DTA analysis, and high energy through calculation. All the three ECPs have good catalytic performance for AP. [Display omitted] • Three new energetic coordination polymers (ECPs) were prepared by the solvothermal method and liquid diffusion method. • The ECPs exhibit satisfactory thermal stability, energetic property, and mechanical sensitivity. • The ECPs show great catalytic performance for the decomposition of ammonium perchlorate. [ABSTRACT FROM AUTHOR]