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1.
A borophosphate hydrate with general composition {(NH4)xCo((3–x)/2)}(H2O)2[BP2O8] · (1 – x) H2O (x ≈ 0.5) was prepared under mild hydrothermal conditions (T = 170 °C). The crystal structure of the purple title compound was refined in space group P65 (no. 170) as a merohedric twin (a = 949.14 pm, c = 1558.25 pm, R1 = 0.037, wR2 = 0.092 for all data). According to preliminary X‐ray investigations, vis‐spectra, and magnetic susceptibility measurements, a second blue coloured variant exhibits a superstructure of the title compound with a change in coordination numbers around cobalt from six and five to six and four. Both phases show reversible de‐/rehydration properties.  相似文献   

2.
In the system ZnO/H3PO4/H2O/1,4‐diazacycloheptane (C5H12N2), a new zincophosphate (ZnPO), (C5H14N2)[Zn3(HPO4)4] ( I ), was prepared by hydrothermal transformation (180 °C) of the known ZnPO hydrate (C5H14N2)[Zn2(HPO4)3]·H2O ( II ). The thermally‐induced transformation is reversible; upon keeping the heterogeneous mixture of I and mother liquor at 80 °C recrystallization of II was observed. Single‐crystal X‐ray crystallography revealed that I possesses a unique three‐dimensional (3D) open‐framework structure built from corner‐linked ZnO4 and HPO4 tetrahedra. The (3,4)‐connected framework of I differs considerably from the 3D open‐framework ZnPO structure of II . Crystal data for I : Monoclinic system, space group Cc (No. 9) , Z = 4, a = 9.1389(6), b = 23.627(2), c = 9.3073(6) Å, β = 109.463(7)°, T = 298 K.  相似文献   

3.
Syntheses, Crystal Structure, and Properties of the Cage‐like, Hexaacidic P12S12N8(NH)6 · 14 H2O and its Salts Li6[P12S12N14] · 26 H2O, (NH4)6[P12S12N14] · 10 H2O, and K6[P12S12N14] · 8 H2O The cage‐like acid P12S12N8(NH)6 · 14 H2O was obtained by the reaction of KSCN with P4S10 via the formation of K6[P12S12N14] · 8 H2O and subsequent ion exchange reactions in aqueous solution. Starting from the acid the salts Li6[P12S12N14] · 26 H2O and (NH4)6[P12S12N14] · 10 H2O were synthesized. According to X‐ray single‐crystal structure analyses the compounds are built up by isosteric P–N cages [P12S12N[3]8N[2]6]6–. Each of them is made up of twelve P3N3 rings, which exclusively exhibit the boat conformation. The cages have the idealized symmetry 2/m3; P12S12N8(NH)6 · 14 H2O: P1, a = 1119.11(7), b = 1123.61(7), c = 1125.80(6) pm, α = 80.186(4), β = 60.391(4), γ = 60.605(4)°, Z = 1; Li6[P12S12N14] · 26 H2O: Fm3, a = 1797.4(1) pm, Z = 4; (NH4)6[P12S12N14] · 10 H2O: P63, a = 1153.2(1), c = 2035.6(2) pm, Z = 2; K6[P12S12N14] · 8 H2O: R3c, a = 1142.37(5), c = 6009.6(3) pm, Z = 6. In the crystal the cages of the acid are crosslinked via hydrate molecules by hydrogen bonds. The cations in the salts show a high‐mobility and are located between the cages.  相似文献   

4.
Employing achiral organic amines (2-methylbenzimidazole and 1,4-diazabicyclo[2.2.2]octane) as the structure-directing agent and ligand, two chiral zincophosphites, [Zn(C(8)H(8)N(2))(HPO(3))] 1 and (C(6)H(13)N(2))[Zn(3)(C(6)H(12)N(2))(HPO(3))(3)(H(2)PO(3))] 2, have been hydro(solvo)-thermally synthesized, crystallizing in the chiral space group P2(1)2(1)2(1). Single-crystal structural analysis reveals that compound 1 consists of alternating ZnO(3)N and HPO(3) units exhibiting a neutral one-dimensional chiral chain. Interestingly, the organic ligands interact with the inorganic chain via hydrogen-bonds in hydrogen-bonded helix fashion. Compound 2, a three-dimensional chiral open framework with 16-MR channels, is formed by the distorted {Zn(3)P(4)} secondary building unit (SBU). The organic amine molecules play dual roles as both ligands and countercations.  相似文献   

5.
(C2H10N2)[BPO4F2] — Strukturbeziehungen zwischen [BPO4F2]2— und [Si2O6]4— Colourless crystals of (C2H10N2)[BPO4F2] were prepared from mixture of ethylendiamine, H3BO3, BF3 · C2H5NH2, H3PO4 and HCl under mild hydrothermal conditions (220 °C). The crystal structure was determined by single crystal methods (triclinic, P1¯ (no. 2), a = 451.85(5) pm, b = 710.20(8) pm, c = 1210.2(2) pm, α = 86.08(1)°, β = 88.52(2)°, γ = 71.74(1)°, Z = 2) and contains infinite tetrahedral zweier‐single‐chains {[BPO4F2]2—} which are isoelectronic (48e) with the polyanions {[Si2O6]4—} of the pyroxene family.  相似文献   

6.
Synthesis and Crystal Structure of the Transition Metal Trimetaphosphimates Zn3[(PO2NH)3]2 · 14 H2O and Co3[(PO2NH)3]2 · 14 H2O The transition metal trimetaphosphimates Zn3[(PO2NH)3]2 · 14 H2O and Co3[(PO2NH)3]2 · 14 H2O were obtained by the reaction of an aqueous solution of Na3(PO2NH)3 · 4 H2O with the respective metal nitrate or halide (molar ratio 1 : 4). The structure of Zn3[(PO2NH)3]2 · 14 H2O was solved by single crystal X‐ray methods. The structure of isotypic Co3[(PO2NH)3]2 · 14 H2O was refined from X‐ray powder diffraction data using the Rietveld method (Zn3[(PO2NH)3]2 · 14 H2O ( 1 ): P 1, a = 743.7(2), b = 955.9(2), c = 980.1(2) pm, α = 102.70(3), β = 90.46(3), and γ = 100.12(3)°, Z = 1; Co3[(PO2NH)3]2 · 14 H2O ( 2 ): P 1, a = 746.05(1), b = 957.06(2), c = 988.51(2) pm, α = 102.162(1), β = 90.044(1), and γ = 99.258(1)°, Z = 1). In 1 and 2 the P3N3 rings of the trimetaphosphimate ions attain a conformation which can be described as a combination of an ideal boat and an ideal twist conformation. The trimetaphosphimate ions act as bridging ligands. Thus chains of alternating M2+ and (PO2NH)33– ions are formed which are interconnected by additional M2+ ions forming electro‐neutral double chains. In the solid these double chains are connected by hydrogen bonds.  相似文献   

7.
A inorganic‐organic hybrid zinc phosphite (C2H3N3)Zn(HPO3) ( 1 ) has been prepared under solvothermal conditions in the presence of 1,2,4‐triazole (trz) ligand.Its structure was determined by single‐crystal X‐ray diffraction, and further characterized by powder X‐ray diffraction (XRD), FTIR spectroscopy, elemental analysis, ICP analysis, thermogravimetric analysis and fluorescent spectrum. It crystallizes in the monoclinic system, space group P21/n, a = 7.5515(6) Å, b = 9.1813(8) Å, c = 10.0125(8) Å, β = 111.267(1)°, V = 646.92(9) Å3, Z = 4. The structure consists of left‐handed and right‐handed helical chains that are connected through bridging oxygen atoms to form a two‐dimensional layer structure with 4.8‐net. The compound exhibits intense photoluminescence upon photo‐excitation at 326 nm.  相似文献   

8.
Bis(tetramethylammonium) dodecahydrododecaborate, [(CH3)4N]2[B12H12], and bis(tetramethylammonium) dodecahydrododecaborate acetonitrile, [(CH3)4N]2[B12H12] · CH3CN, were synthesized and characterized via Infrared, 1H and 11B NMR spectroscopy. [(CH3)4N]2[B12H12] crystallizes isopunctual to the alkali metal dodecaborates. The crystal structure of [(CH3)4N]2[B12H12] · CH3CN was determined from single crystal data and refined in the orthorhombic crystal system (Pcmn, no. 62, a = 898.68(8), b = 1312.85(9) c = 1994.5(1) pm, R(|F| , 4σ) = 5.9%, wR(F2) = 18.3%). Here, the geometry of the dodecaborate anion is that of an almost ideal icosahedron, less distorted than most other dodecaborates known. By low‐temperature Guinier‐Simon diffractometry phase transitions were detected for [(CH3)4N]2[B12H12] and [(CH3)4N]2[B12H12] · CH3CN at –70 and –15 °C, respectively.  相似文献   

9.
Two new hybrid fluorides, {[(C2H4NH3)3NH]4+}2 · (H3O)+ · [Al7F30]9– ( I ) and {[(C2H4NH3)3NH]4+}2 · [Al7F29]8– · (H2O)2 ( II ), are synthesized by solvothermal method. The structure determinations are performed by single crystal technique. The symmetry of both crystals is triclinic, sp. gr. P 1, I : a = 9.1111(6) Å, b = 10.2652(8) Å, c = 11.3302(8) Å, α = 110.746(7)°, β = 102.02(1)°, γ = 103.035(4)°, V = 915.9(3) Å3, Z = 1, R = 0.0489, Rw = 0.0654 for 2659 reflections, II : a = 8.438(2) Å, b = 10.125(2) Å, c = 10.853(4) Å, α = 106.56(2)°, β = 96.48(4)°, γ = 94.02(2)°, V = 877.9(9) Å3, Z = 1, R = 0.0327, Rw = 0.0411 for 3185 reflections. In I , seven corner‐sharing AlF6 octahedra form a [Al7F30]9– anion with pseudo 3 symmetry; such units are found in the pyrochlore structure. The aluminum atoms lie at the corners of two tetrahedra, linked by a common vertex. In II , similar heptamers are linked in order to build infinite (Al7F29)n8– chains oriented along a axis. In both compounds, organic moieties are tetra protonated and establish a system of hydrogen bonds N–H…F with four Al7F309– heptamers in I and with three inorganic chains in II .  相似文献   

10.
Synthesis, Structure, and Properties of Some Selenidostannates. II. [(C2H5)3NH]2Sn3Se7 · 0,25 H2O and [(C3H7)2NH2]4Sn4Se10 · 4 H2O The new selenidostannate hydrates [(C2H5)3NH]2Sn3Se7 · 0.25 H2O ( I ) and [(C3H7)2NH2]4Sn4Se10 · 4 H2O ( II ) were synthesized from an aqueous suspension of triethylammonium (tripropylammonium), tin, selenium I and in addition sulfur II at 130 °C. I crystallizes at ambient temperature in the monoclinic space group P21/n (a = 2069,3(4) pm, b = 1396,6(3) pm, c = 2342,8(5) pm, β = 114,68(3)°, Z = 8) and is characterized by two different anions, chains from edge‐sharing [Se3Se7]2– units and nets from trigonal SnSe5 bipyramids. II crystallizes at ambient temperature in the tetragonal space group I41/amd (a = 2150,0(3) pm, c = 1174,4(2) pm, Z = 4) and contains adamantane like [Sn4Se10]4–‐cages. The UV‐VIS spectra of the selenidostannates demonstrate that the absorption edges red shift as the dimensionality of the compounds is increased.  相似文献   

11.
Synthesis, Crystal Structure and Thermal Behaviour of Fluoroaluminates of the Composition (NH4)[M(H2O)6](AlF6) (M = Zn, Ni), [Zn(H2O)6][AlF5(H2O)], and (PyH)4[Al2F10] · 4 H2O Four new fluoroaluminates were obtained from fluoroacidic solutions of respective metal salts. The compounds of zinc ( I a : P21/c, a = 12.688(3), b = 6.554(1), c = 12.697(3) Å, β = 95.21(3)°, V = 1051.5(4) Å3, Z = 4) and nickel ( I b : P21/c, a = 12.685(3), b = 6.517(1), c = 12.664(2)Å, β = 94.55(2)°, V = 1043.6(4) Å3, Z = 4) are isotypic and represent a new structure type consisting of two different cations, NH4+ and [M(H2O)6]2+ and [AlF6]3–‐anions. [Zn(H2O)6][AlF5(H2O)] ( II : C2/m, a = 10.769(2), b = 13.747(3), c = 6.487(1)Å, β = 100.02(3)°, V = 945.7(3) Å3, Z = 4) is characterized by a H2O/F‐disorder in the [AlF5(H2O)]‐octahedra in two trans positions. In (PyH)4[Al2F10] · 4 H2O ( III : Cmc21, a = 15.035(3), b = 20.098(4), c = 12.750(4) Å, V = 5364(2) Å3, Z = 8), bioctahedral [Al2F10]4– anions have been found for the first time. The structures are described and discussed in comparison. The new compounds were used as precursors in order to obtain new AlF3‐phases. However, the thermal decomposition did not result in the formation of any new metastable AlF3‐phase. Instead, phase mixtures of either α‐AlF3 and β‐AlF3 or AlF3 and MF2 were obtained.  相似文献   

12.
Diammonium tricyanomelaminate dihydrate [NH4]2[C6N9H] · 2 H2O ( 1 ) and dimelaminium tricyanomelaminate melamine dihydrate [C3N6H7]2[C6N9H] · C3N6H6 · 2 H2O ( 2 ) were obtained by metathesis reactions from Na3[C6N9] in aqueous solution and characterized by single‐crystal X‐ray diffraction and 15N solid‐state NMR spectroscopy ( 1 ). Both salts contain mono‐protonated tricyanomelaminate (TCM) anions and crystallize as dihydrates. Considering charge balance requirements, the crystal structure of 1 (C2/c, a = 3181.8(6) pm, b = 360.01(7) pm, c = 2190.4(4) pm, β = 112.39(3)°, V = 2319.9(8) 106 · pm3) can best be described by assuming a random distribution of an ammonium ion – crystal water pair over two energetically similar sites. Apart from two melaminium cations, 2 (P21/c, a = 674.7(5) pm, b = 1123.6(5) pm, c = 3400.2(5) pm, β = 95.398(5), V = 2566(2) 106 · pm3) contains one neutral melamine per formula unit acting as an additional “solvent” molecule and yielding a donor‐acceptor type of π–stacking interaction.  相似文献   

13.
Synthesis, Crystal Structure, and Vibrational Spectra of cis ‐(CH2Py2)[ReBr4Py2]2 · (CH3)2CO By reaction of (n‐Bu4N)2[ReBr6] with pyridine and (n‐Bu4N)BH4 in dichloromethane halogeno‐pyridine‐rhenium(III)complexes are formed and purified by chromatography. X‐ray structure determination on a single crystal has been performed of cis‐(CH2Py2)[ReBr4Py2]2 · (CH3)2CO (monoclinic, space group P21/c, a = 15.0690(9), b = 8.3337(8), c = 35.588(4) Å, β = 96.409(7), Z = 4). Based on the molecular parameters of the X‐ray structure determination and assuming C2 point symmetry for the anion cis‐[ReBr4Py2] the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants are in the Br–Re–Br axis fd(ReBr) = 1.49, in the asymmetrically coordinated N′–Re–Br · axes fd(ReBr · ) = 1.03 und fd(ReN′) = 2.52 mdyn/Å.  相似文献   

14.
Isotypic Borophosphates MII(C2H10N2)[B2P3O12(OH)] (MII = Mg, Mn, Fe, Ni, Cu, Zn): Compounds containing Tetrahedral Layers The isotypic compounds MII(C2H10N2) · [B2P3O12(OH)] (MII = Mg, Mn, Fe, Ni, Cu, Zn) were prepared under hydrothermal conditions (T = 170 °C) from mixtures of the metal chloride (chloride hydrate, resp.), Ethylenediamine, H3BO3 and H3PO4. The orthorhombic crystal structures (Pbca, No. 61, Z = 8) were determined by X‐ray single crystal methods (Mg(C2H10N2)[B2P3O12(OH)]: a = 936.81(2) pm, b = 1221.86(3) pm, c = 2089.28(5) pm) and Rietveld‐methods (MII = Mn: a = 931.91(4) pm, b = 1234.26(4) pm, c = 2129.75(7) pm, Fe: a = 935.1(3) pm, b = 1224.8(3) pm, c = 2088.0(6) pm, Ni: a = 939.99(3) pm, b = 1221.29(3) pm, c = 2074.05(7) pm, Cu: a = 941.38(3) pm, b = 1198.02(3) pm, c = 2110.01(6) pm, Zn: a = 935.06(2) pm, b = 1221.33(2) pm, c = 2094.39(4) pm), respectively. The anionic part of the structure contains tetrahedral layers, consisting of three‐ and nine‐membered rings. The MII‐ions are in a distorted octahedral or tetragonal‐bipyramidal [4 + 2] (copper) coordination formed by oxygen functions of the tetrahedral layers. The resulting three‐dimensional structure contains channels running along [010]. Protonated Ethylenediamine ions are fixed within the channels by hydrogen bonds.  相似文献   

15.
由于在电学、磁学、光学、吸附、离子交换和催化等领域具有潜在的应用价值,具有开放骨架结构的金属磷酸盐的合成一直受到人们的广泛关注。在这些磷酸盐微孔化合物中,磷酸锌晶体是拓扑结构最为丰富的一种犤1犦。自从Stucky等犤2犦报道具有SOD、Li-ABW、FAU等已知结构磷酸锌的合成以来,已经有近百种具有0-D犤3,4犦,1-D犤5,6犦,2-D犤7~9犦,3-D犤10~13犦结构的磷酸锌被成功地合成出来。其中令人瞩目的是具有螺旋孔道的手性磷酸锌犤14犦以及具有二十四元环孔道的两种微孔磷酸锌化合物犤15,16犦的合成。这些化合物大多是采用水热技术以有…  相似文献   

16.
Two novel borophosphates, MII(C4H12N2)[B2P3O12(OH)] (MII = Co, Zn), exhibiting open frameworks, have been synthesized by hydrothermal reactions (T = 165 °C). The crystal structures of the isotypic compounds have been determined both at 293 K (orthorhombic, Ima2 (no. 46), Z = 4; MII = Co: a = 12.4635(4) Å, b = 9.4021(4) Å, c = 11.4513(5) Å, V = 1341.90 Å3, R1 = 0.0202, wR2 = 0.0452, 2225 observed reflections with I > 2σ(I); MII = Zn: a = 12.4110(9) Å, b = 9.4550(5) Å, c = 11.4592(4) Å, V = 1344.69 Å3, R1 = 0.0621, wR2 = 0.0926, 1497 observed reflections with I > 2σ(I)). Distorted CoO6‐octahedra and ZnO5‐square‐pyramids, respectively, share common oxygen‐corners with BO4‐, PO4‐ and (HO)PO3‐tetrahedra. The tetrahedral groups are linked via common corners to form infinite loop‐branched borophosphate chains [B2P3O12(OH)4–]. The open framework of MII‐coordination polyhedra and tetrahedral borophosphate chains contains a three‐dimensional system of interconnected structural channels running along [100], [011] and [011], respectively, which are occupied by di‐protonated piperazinium ions.  相似文献   

17.
A novel borophosphate‐hydrate, (Ni3–xMgx)[B3P3O12(OH)6] · 6 H2O (x ≈ 1.5), has been prepared by hydrothermal synthesis (T = 170 °C) from a mixture of NiCl2 · 6 H2O, Mg(OH)2, B2O3 and H3PO4. The crystal structure was determined at 293 K from single‐crystal X‐ray diffraction data (trigonal, R3c (no. 167), a = 14.957(10) Å, c = 13.812(6) Å, V = 2676(2) Å3, Z = 6, R1 = 0.0276, wR2 = 0.0714 for 779 observed reflections with I > 2σ(I)). The crystal structure contains unbranched six‐membered rings [B3P3O12(OH)6]6– of alternating corner linked borate and phosphate tetrahedra, which are stacked along [001] and connected via MIIO2(OH)2(H2O)2 coordination polyhedra. Hydrogen bonding between the tetrahedral six‐membered rings and MIIO2(OH)2(H2O)2 octahedra leads to a further cross‐linking. With respect to the arrangement of isolated six‐membered tetrahedral rings the crystal structure of this borophosphate‐hydrate is closely related to the cyclo‐hexasilicate dioptase, Cu6[Si6O18] · 6 H2O.  相似文献   

18.
Supramolecular aspects on Te(OH)6 as substitute for crystal‐water in adenine hydrate complexes and the first disodium ditellurate(VI) are reported. The co‐crystallate [Te(OH)6 · 2 adenine · 4 H2O] ( 1 ) has been prepared in 41% yield from the 1 : 1 mixing of Te(OH)6 with the nitrogenous base adenine. The adduct of infinite stacks of adenine molecules, Te(OH)6 and water not only proves that Te(OH)6 mimicks the role of water in the related hydrate adenine · 3 H2O but also shows that the inclusion of Te(OH)6 raises the number of HO–H and N–HO contacts and therefore increases the distance between the adenine rings to 3.31 Å in 1 in comparison to that in adenine trihydrate (3.22 Å). Additionally, the disodium ditellurate(VI) aggregate {[Te2(O)2(OH)6(ONa)2]2 [NaOH · 12.5 H2O]} ( 2 ) resulted from the reaction of 1 with 2 molar equivalents of aqueous NaOH. Dinuclear 2 represents the first X‐ray diffraction characterized example of a sodium tellurate(VI) constructed from [Te2O4(OH)6]2– dianions.  相似文献   

19.
Polymeric Iodoplumbates – Synthesis and Crystal Structures of (Pr3N–C2H4–NPr3)[Pb6I14(dmf)2] · 4 DMF, (Pr3N–C2H4–NPr3)[Pb(dmf)6][Pb5I14] · DMF, and (Me3N–C2H4–NMe3)2[Pb2I7]I (Pr3N–C2H4–NPr3)[Pb6I14(dmf)2] · 4 DMF ( 1 ) and (Pr3N–C2H4–NPr3)[Pb(dmf)6][Pb5I14] · DMF ( 2 ) have almost the same composition, but completely different structures. Both compounds are formed selectively depending on the reaction and crystallization conditions. In 2 the PbII atoms are coordinated either by six bridging I ligands in the two-dimensional [Pb5I14]4– network or by six DMF ligands in the [Pb(dmf)6]2+ cations. In contrast, (Me3N–C2H4–NMe3)2[Pb2I7]I ( 3 ) contains non-coordinating I anions between the iodoplumbate layers. The iodoplumbate anions in 2 and 3 consist of face and corner sharing PbI6 octahedra, whereas in 1 PbI6 and PbI5(dmf) octahedra share common edges to form a one-dimensional polymeric section of the PbI2 structure. (Pr3N–C2H4–NPr3)[Pb6I14(dmf)2] · 4 DMF ( 1 ): Space group P1, a = 920.1(3), b = 1597.2(5), c = 1613.9(4) pm, α = 66.02(2), β = 84.53(2), γ = 85.99(2)°, V = 2156(1) · 106 pm3; (Pr3N–C2H4–NPr3)[Pb(dmf)6][Pb5I14]·DMF ( 2 ): Space group P21, a = 1201.21(9), b = 3031.1(2), c = 1294.96(9) pm, β = 108.935(7)°, V = 4459.8(5) · 106 pm3; (Me3N–C2H4–NMe3)2[Pb2I7]I ( 3 ): Space group Pnma, a = 2349.9(2), b = 1623.83(9), c = 980.75(7) pm, V = 3742.4(5) · 106 pm3.  相似文献   

20.
Complex Hydroxides of Chromium: Na9[Cr(OH)6]2(OH)3 · 6 H2O and Na4[Cr(OH)6]X · H2O (X = Cl, (S2)1/2) – Synthesis, Crystal Structure, and Thermal Behaviour Green plate‐like crystals of Na9[Cr(OH)6]2(OH)3 · 6 H2O (triclinic, P1, a = 872.9(1) pm, b = 1142.0(1) pm, c = 1166.0(1) pm, α = 74.27(1)°, β = 87.54(1)°, γ = 70.69(1)°) are obtained upon slow cooling of a hot saturated solution of CrIII in conc. NaOH (50 wt%) at room temperature. In the presence of chloride or disulfide the reaction yields green prismatic crystals of Na4[Cr(OH)6]Cl · H2O (monoclinic, C2/c, a = 1138.8(2) pm, b = 1360.4(1) pm, c = 583.20(7) pm, β = 105.9(1)°) or green elongated plates of Na4[Cr(OH)6](S2)1/2 · H2O (monoclinic, P21/c, a = 580.8(1) pm, b = 1366.5(3) pm, c = 1115.0(2) pm, β = 103.71(2)°), respectively. The latter compounds crystallize in related structures. All compounds can be described as distorted cubic closest packings of the anions and the crystal water molecules with the cations occupying octahedral sites in an ordered way. The thermal decomposition of the compounds was investigated by DSC/TG or DTA/TG and high temperature X‐ray powder diffraction measurements. In all cases the final decomposition product is NaCrO2.  相似文献   

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