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We provide the material synthesis method, crystal structure information, and characterization of a novel mixed-valent metal oxide KIn0.33IIITe0.67VITe2IVO7, closely related to zirconolite (CaZrTi2O7), a radioactive waste immobilized material, having a 3D framework. The reported metal oxide containing an alkali-metal cation (K+), main-group cation (In3+), tellurate, and tellurite has been synthesized as both single crystals and a pure polycrystalline phase through a hydrothermal synthesis method. Single-crystal X-ray diffraction indicates that KIn0.33Te2.67O7 crystallizing in the orthorhombic space group Cmcm (No. 63) reveals a 3D framework structure with a 1D channel consisting of Te/InO6 octahedra and TeO4 polyhedra. An interesting transition reaction from KIn0.33Te2.67O7 to KIn(TeO3)2 under hydrothermal conditions at 230 °C is discussed.

Five ternary and quaternary Zintl phases in the solid-solution Ca11-xAxSb10-yGez (A = Na, Li; 0.06(3) ≤ x ≤ 0.17(5), 0.19(1) ≤ y ≤ 0.55(1), 0.13(1) ≤ z ≤ 0.22(1)) system have been successfully synthesized by both of the arc-melting and the molten Pb metal-flux reactions. The crystal structure of these title compounds was characterized by powder and single-crystal X-ray diffractions analyses, and all title compounds crystallized in the Ho11Ge10-type phase in the tetragonal space group I4/mmm (Z = 4, Pearson code tI84). The complex crystal structure can be described as an assembly of 1) three kinds of cationic polyhedra centered by three different Sb and 2) the cage-shaped anionic frameworks built through the connection of two types of Sb. The newly substituted p-type double dopants of the cationic (Na and Li) and anionic (Ge) elements displayed particular site preferences, which were successfully explained by either the size-factor criterion based on the atomic size or the electronic-factor criterion based on the electronegativity of an element. Quite interestingly, as the reaction conditions were changed, the morphology shift of single crystals in Ca10.94(3)Na0.06Sb9.58(1)Ge0.21 occurred from a cubic-shaped to a hummocky-type, to a hopper-type, and eventually to an octahedral-shaped crystal, just like the Yakutian kimberlite diamonds. Moreover, we firmly believe that the inclusion of the p-type Ge dopant for Sb was crucial to trigger this type of morphology shift and complete the octahedral-shaped morphology in the overall crystal-growth mechanism. The theoretical calculations using a DFT method rationalized the observed site preference of Na and the electronic effect of the p-type Ge dopants. The Seebeck coefficient measurements for Ca10.88(4)Li0.12Sb9.45(1)Ge0.21 indicated that some portions of electron charge carriers were effectively eliminated by the p-type double dopants using Li and Ge.

Crystals of two strontium niobium oxyfluorides, Sr2Nb6O13F8·4H2O and Sr3Nb2O2F12·2H2O, have been grown in phase pure forms via hydrothermal reactions using SrCO3, Nb2O5, and an aqueous HF solution. Single-crystal X-ray diffraction suggests that Sr2Nb6O13F8·4H2O, crystallizing in the orthorhombic centrosymmetric space group, Pbam (No. 55), reveals a new variant of the three-dimensional tungsten bronze structure with three-, four-, and five-membered rings that are composed of corner-sharing NbO2(O/F)2F2, NbO4(O/F)F, NbO3(O/F)3, and SrO3F6 groups. Sr3Nb2O2F12·2H2O with the noncentrosymmetric polar space group, Cmc21 (No. 36), however, reveals a molecular structure consisting of Nb(O/F)2F5 pentagonal bipyramids and two unique Sr2+ cations interacting with F, O/F, and water molecules. Band gaps calculated by the Kubelka-Munk function based on the ultraviolet-visible diffuse-reflectance spectra of Sr2Nb6O13F8·4H2O and Sr3Nb2O2F12·2H2O are estimated to be ca. 3.22 and 4.11 eV, respectively, in which the values are related to the contents of electronegative F atoms and the Nb-O(F)-Nb bond angles influenced by structural distortion. An interesting phase transition reaction from Sr3Nb2O2F12·2H2O to thermodynamically more stable Sr2Nb6O13F8·4H2O occurs under a hydrothermal condition.

A novel guanidinium-templated ultraviolet (UV) nonlinear optical zinc carbonate crystal, [C(NH

A series of quaternary and quinary Zintl phase thermoelectric (TE) compounds, Ca5–xYbxAl2–yInySb6 (3.07(1) ≤ x ≤ 4.88(2); 0.16(2) ≤ y ≤ 2.00), containing Al/In mixed sites as well as Ca/Yb mixed si...

We provide the material synthesis method, crystal structure information, and characterization of a novel mixed-valent metal oxide KIn

Crystals of two strontium niobium oxyfluorides, Sr

Two novel bismuth oxyfluoride nitrates, Bi2OF3(NO3) and Bi6O6F5(NO3), have been synthesized via hydrothermal reactions. Whereas Bi2OF3(NO3) crystallizes in the centrosymmetric (CS) hexagonal space ...

Lone pair cation-based novel coordination compounds Sn[(pdc)(H2O)] (Sn–I) and (H2bpy)[Bi(pdc)2(Hpdc)]·5H2O (Bi–I) (pdc = pyridine-2,6-dicarboxylate; bpy = 4,4′-bipyridine) were synthesized through ...

A series of lithium metal selenites, Li6M(SeO3)4 (M = Co, Ni, and Cd) and Li2Zn(SeO3)2, were synthesized by hydrothermal and solid-state reactions. Li6M(SeO3)4 is composed of Li+ cations, MO6 octahedra, and SeO3 polyhedra, while Li2Zn(SeO3)2 consists of Li+, Zn(Li)O4 tetrahedra, and SeO3 polyhedra. Isostructural Li6Co(SeO3)4 and Li6Ni(SeO3)4 crystallize in the rhombohedral space group R3, forming a three-dimensional distorted cubic lattice. Li2Zn(SeO3)2 crystallizes in the orthorhombic space group Pbam and reveals a layered structure in the bc plane. Li6Cd(SeO3)4 revealing a unidimensional structure crystallizes in the polar non-centrosymmetric space group C2, attributed to the parallel alignment of distorted CdO6 octahedra. The direct-current magnetic susceptibility measurements unveil that Li6Co(SeO3)4 is a canted antiferromagnet with TN = 25 K, while Li6Ni(SeO3)4 undergoes an antiferromagnetic transition at TN = 54 K, having a negligible canted moment. The weak ferromagnetism observed in Li6Co(SeO3)4 ...

A novel lithium-rich transition metal selenite, Li13Mn(SeO3)8, that is composed of a Jahn–Teller distortive cation, Mn3+, in the high spin d4 state, and a second-order Jahn–Teller (SOJT) distortive lone pair cation, Se4+, has been synthesized via hydrothermal and high temperature solid state reactions. The selenite is classified as a molecular compound consisting of MnO6 octahedra, SeO3 trigonal pyramids, and Li+ cations. Considering the Li–O interactions, the structure of Li13Mn(SeO3)8 may be described as a pseudo-three-dimensional framework as well. The title compound is thermally stable up to 500 °C and starts decomposing above the temperature attributable to the volatilization of SeO2. While the MnO6 octahedra in Li13Mn(SeO3)8 exhibit six identical Mn–O bond distances at room temperature due to the dynamic Jahn–Teller effect, a clear elongation of two Mn–O bonds along a specific direction is observed at 100 K. A series of isostructural selenites with different transition metals, i.e., Li13M(SeO3)8 (M ...

Four new metal iodates, namely, NaLn(IO3)4 (Ln = La, Ce, Sm, and Eu), and a series of NaLa(IO3)4:Ln3+ (Ln = Sm and Eu) solid solutions were synthesized through hydrothermal reactions. The structures of the title compounds are similar to that of NaY(IO3)4 crystallizing in the acentric monoclinic space group Cc. The iodate materials reveal layered structures composed of LnO8 square antiprisms and IO3 polyhedra, in which each layer is connected by the I···O interactions. NaLa(IO3)4 suggests a great potential as a matrix for optical source attributed to its acentricity and broad transparency from visible to mid-IR region. The photoluminescence properties depending on the concentration of Sm3+ reveal that NaLa(IO3)4:Sm3+ undergoes a self-quenching relaxation over 7 mol % of Sm3+ by dipole–quadrupole interactions. Attributable to the asymmetric coordination environment of Ln3+, stronger electric dipole transitions compared to magnetic dipole transitions were observed for both compounds. In addition, the materia...

The Zintl phase solid-solution Ca11−xYbxSb10−yGez (0 ≤ x ≤ 9; 0 ≤ y ≤ 3; 0 ≤ z ≤ 3) system with the cationic/anionic multisubstitution has been synthesized by molten Sn metal flux and arc-melting methods. The crystal structure of the nine title compounds were characterized by both powder and single-crystal X-ray diffractions and adopted the Ho11Ge10-type structure with the tetragonal space group I4/mmm (Z = 4, Pearson Code tI84). The overall isotypic structure of the nine title compounds can be illustrated as an assembly of three different types of cationic polyhedra sharing faces with their neighboring polyhedra and the three-dimensional cage-shaped anionic frameworks consisting of the dumbbell-shaped Sb2 units and the square-shaped Sb4 or (Sb/Ge)4 units. During the multisubstitution trials, interestingly, we observed a metal-to-semiconductor transition as the Ca and Ge contents increased in the title system from Yb11Sb10 to Ca9Yb2Sb7Ge3 (nominal compositions) on the basis of a series of thermoelectric p...

Three new quaternary lithium metal tellurites, Li3MTe4O11 (M = Al, Ga, and Fe), have been synthesized through hydrothermal and solid-state reactions by heating a mixture of LiOH·H2O, TeO2, and M2O3. The structures of the title compounds have been determined by single-crystal and powder X-ray diffraction. Li3MTe4O11 reveal three-dimensional (3D) frameworks that consist of MO6 octahedra, TeO3 trigonal pyramids, and TeO4 polyhedra. The variable coordination mode of Te4+ within the framework leads to the formation of 1D channels that host Li+ cations on both tetrahedral and octahedral sites. The bulk and grain boundary Li+ ion conductivities for a Li3FeTe4O11 pellet in open air are estimated to be 1.0 × 10–4 and 2.7 × 10–6 S cm–1, respectively, at room temperature from the impedance profile analysis. A lower activation energy of 19.9 kJ mol–1 is obtained for the system, which is similar to that of Li10GeP2S12 (24 kJ mol–1). Detailed characterizations such as thermal, spectroscopic, and magnetic properties for...

A noncentrosymmetric (NCS) titanium-organic compound, [H2N(CH3)2]TiO{[NC5H3(CO2)2][NC5H4(CO2)]} (CAUMOF-18), has been synthesized by a solvothermal reaction. The aligned unidimensional polar chain structure of CAUMOF-18 consisting of corner-shared distorted TiO5N2 pentagonal bipyramids is attributed to strong hydrogen-bonding and π-π interactions. CAUMOF-18 reveals a very strong second-harmonic-generation efficiency of 400 times that of α-SiO2 and is phase-matchable (type I). Water-molecule-driven reversible centricity conversion and topotactic transformation to TiO2 microrods for CAUMOF-18 are also presented.

Two new quaternary molybdenum(VI) antimony(III) oxides, ZnMoSb2O7 and CdMoSb4O10, have been synthesized in phase-pure form. The title compounds consist of highly polarizable cations, i.e., d(0) (Mo(6+)) and d(10) (Zn(2+) or Cd(2+)), and lone-pair cations (Sb(3+)). ZnMoSb2O7 exhibits a three-dimensional framework with ZnO4, MoO4, and SbO4 polyhedra in the polar space group P21, whereas CdMoSb4O10 exhibits one-dimensional tubule structures with CdO6, MoO4, and SbO3 polyhedra in the space group P21/m. Several synthetic efforts suggest that the the dissimilar radii of Zn(2+) and Cd(2+) that can accommodate polyhedra of Sb(3+) cations influence the stoichiometry as well as the centricity for the reported materials. Spectroscopic, thermal, and elemental analyses are reported along with dipole moment calculations. Nonlinear optical properties and their structural origin are examined for polar ZnMoSb2O7 as well.

Three new metal vanadium tellurites, MVTe2O8 (M = Al, Ga, and Mn) have been synthesized through standard solid-state and hydrothermal reactions. Crystal structure analyses using X-ray diffraction reveal that the isostructural materials exhibit layered structures consisting of MO6, TeO4, and VO4 polyhedra. The corner-sharing of MO6 octahedra results in one-dimensional (1-D) zigzag chains that are further interconnected by tetrameric Te4O12 units and the VO4 tetrahedra to complete a layered structure. Detailed structural analysis suggests that the unit-cell volumes and the very long Te(2)-O(2) bond distances in MVTe2O8 are closely related to the ionic radii of M(3+) cations. Additional characterizations such as ultraviolet-visible light (UV-vis) and infrared spectroscopies, thermogravimetric analyses, and electron paramagnetic resonance measurements were performed. The temperature-dependent magnetic susceptibility measurements on MnVTe2O8 suggest that the material behaves like a three-dimensional (3-D) antiferromagnet with T(N) = 30 K, although the structure consists of a zigzag S = 2 spin chain.

Four novel transition metal oxyfluorides, [Zn(pz)3][MoO2F4]·0.1H2O (1), [Zn(pz)2F2][Zn(pz)3]2[WO2F4]2 (2), [Cd(pz)4][Cd(pz)4(H2O)][MoO2F4]2·0.625H2O (3), and [Zn(mpz)3]2[MoO2F4]2 (4) (pz = pyrazole; mpz = 3-methyl pyrazole) have been synthesized. Compounds 1 and 4 contain helical chains. Compound 2 accommodates zigzag chains, and compound 3 has quasi-one-dimensional linear chains. The variable chain structures are found to be attributable to the different structure-directing anionic groups and hydrogen bonding interactions. Compound 4 crystallized in the noncentrosymmetric (NCS) polar space group, Pna21, is nonphase-matchable (Type I), and reveals a moderate second-harmonic-generation (SHG) efficiency (10 × α-SiO2). The observed SHG efficiency of compound 4 is due to the small net polarization occurring from the arrangement of ZnN3F2 trigonal bipyramids. Spectroscopic and thermal characterizations along with calculations for the title materials are reported.

A series of lithium metal selenites, Li

Both single crystals and pure polycrystalline samples of three new quaternary alkali metal molybdenum selenites, Na2Mo2O5(SeO3)2, K2Mo2O5(SeO3)2, and Rb2Mo3O7(SeO3)3, have been synthesized through hydrothermal and solid-state reactions using A2CO3 (A = Na, K, and Rb), MoO3, and SeO2 as reagents. The frameworks of all three materials consist of both families of second-order Jahn-Teller distortive cations, i.e., the d(0) cation (Mo(6+)) and the lone pair cation (Se(4+)). Although the extent of framework distortions and the resulting occupation sites of alkali metal cations are dissimilar, Na2Mo2O5(SeO3)2 and K2Mo2O5(SeO3)2 exhibit similar three-dimensional networks that are composed of highly asymmetric Mo2O11 dimers and SeO3 polyhedra. Rb2Mo3O7(SeO3)3 reveals a two-dimensional structure that is built with Mo3O15 trimers and SeO3 intralayer linkers. Close structural examinations suggest that the structure-directing effect of alkali metal cations is significant in determining the framework distortions and the dimensions of the molybdenum selenites. UV-vis diffuse reflectance and infrared spectroscopy, thermogravimetric analyses, and ion-exchange reactions are reported, as are out-of-center distortion and dipole moment calculations.

A novel lithium-rich transition metal selenite, Li

Four new metal iodates, namely, NaLn(IO

The Zintl phase solid-solution Ca

Four new alkali metal indium tellurites, NaIn(TeO3)2, KIn(TeO3)2, RbInTe3O8, and CsInTe3O8, have been prepared through hydrothermal and solid state synthesis reactions using corresponding alkali metal carbonates, In2O3 [or In(NO3)3·xH2O], and TeO2. The structures of the reported materials have been determined by powder and single crystal X-ray diffraction. The mixed indium tellurites reveal a rich structural chemistry with different channel structures. NaIn(TeO3)2 shows 8-membered rings, whereas stoichiometrically similar KIn(TeO3)2 exhibits both 8- and 12-membered rings in the frameworks. Isostructural RbInTe3O8 and CsInTe3O8 reveal three-dimensional frameworks consisting of InO6, TeO3, and TeO4 groups. Close structural examination suggests that the alkali metal cation size and variable coordination modes of Te4+ cations cooperatively influence the framework geometries of the new mixed metal tellurites. Detailed characterizations including spectroscopic, elemental, and thermal analyses are introduced. Lo...

Two new sodium tellurium oxide materials, β-Na2Te4O9 and Na2Te2O6·1.5H2O, have been synthesized through hydrothermal reactions using Na2CO3, TeO2, and H2TeO4·2H2O as reagents. The structures of the novel materials have been determined by single crystal X-ray diffraction. β-Na2Te4O9 is a new polymorph of ternary tellurite that is showing a three-dimensional framework structure containing only TeO4 polyhedra. Na2Te2O6·1.5H2O reveals an anionic layered backbone composed of Te6+O6 octahedra and Te4+O5 polyhedra. Thermogravimetric analyses and powder X-ray diffractions at different temperatures suggest that the frameworks of β-Na2Te4O9 and Na2Te2O6·1.5H2O are thermally stable up to 480 and 400 °C, respectively. The Na+ cations in between the anionic layers in Na2Te2O6·1.5H2O are completely replaced by Li+ cations through an ion-exchange reaction. The UV–vis diffuse reflectance and infrared spectra, elemental analyses, and local dipole moment calculations are also reported.