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1.
The crystal structure of a new highly decationated representative of the eudialyte group has been established (R = 0.055, 1734 |F|). The mineral is described by the simplified formula (H3O)9Na2(K, Ba,Sr)2Ca6Zr3[Si26O66(OH)6](OH)3Cl · H2O (Z = 3). The unit-cell parameters are a = 14.078(3) Å, c = 31.24(1) Å; V = 5362 Å3; sp. gr. R3. Being chemically and structurally related to the hydrated analogues studied previously (in particular, to potassium oxonium eudialyte), the new mineral differs from its analogues in that it has a higher degree of Na-and Fe-cation depletion. The replacement of 3/4 of Na cations by loose and mobile H3O groups results in structure destabilization, which is seen from the high values of the thermal parameters of the atoms and the loss of the symmetry plane. 相似文献
2.
A. S. Antsyshkina G. G. Sadikov V. S. Sergienko A. L. Poznyak 《Crystallography Reports》2004,49(4):643-648
The crystal structure of the SrFe(Edta)Cl · 5H2O (I) complex is determined. The crystals are monoclinic, a = 7.530(4) Å, b = 10.575(3) Å, c = 23.308(10) Å, β = 95.75(4)°, Z = 4, and space group P21/c. The structural units of I are infinite ribbons of the molecular type that are formed by tetranuclear fragments. A tetranuclear fragment involves the centrosymmetric positively charged dimer group [Sr(H2O)4Cl] 2 2+ at the center and the [Fe(Edta)(H2O)]? anionic complexes, which compensate for the positive charge of the dimer group, at the periphery. These constituents are bound via bridging oxygen atoms of the Edta ligands. The coordination number of the Sr atom is nine. The Sr-O bond lengths lie in the range between 2.552 and 2.766 Å, the Sr-Cl bond length is 3.216(3) Å, and the Sr?Sr distance is 4.371(1) Å. The parameters of the [Fe(Edta)(H2O)]? group are within the range of values observed in such complexes: Fe-O, 1.996–2.086(3) Å; Fe-O(w), 2.110(4) Å; and Fe-N, 2.289(4) and 2.327(4) Å. Separate ribbons are linked by hydrogen bonds involving all H2O molecules and terminal oxygen atoms of the Edta ligand. 相似文献
3.
A. P. Topnikova E. L. Belokoneva O. V. Dimitrova A. S. Volkov 《Crystallography Reports》2016,61(6):940-944
Crystals of a new polar borate Na2Ce2[BO2(OH)][BO3]2 · H2O were prepared by hydrothermal synthesis. The crystals are orthorhombic, a = 7.2295(7) Å, b = 11.2523(8) Å, c = 5.1285(6) Å, Z = 2, sp. gr. C2mm (Amm2), R = 0.0253. The formula of the compound was derived from the structure determination. The Ce and Na atoms are coordinated by nine and six O atoms, respectively. The Ce position is split, and a small amount of Ce is incorporated into the Na1 site with the isomorphous substitution for Na. The anionic moieties exist as isolated BO3 and BO2(OH) triangles. The planes of the BO2(OH) triangles with mm2 symmetry are parallel to the ab plane. The planes of the BO3 triangles with m symmetry are perpendicular to the ab plane and are rotated in a diagonal way. The splitting of the Ce positions and the polar arrangement of the BO2(OH) triangles, water molecules, and Na atoms are observed along the polar a axis. The new structure is most similar to the new borate NaCa4[BO3]3 (sp. gr. Ama2), in which triangles of one type are arranged in a polar fashion along the c axis. Weak nonlinear-optical properties of both polar borates are attributed to the quenching of the second-harmonic generation due to the mutually opposite orientation of two-thirds of B triangles in the unit cell. 相似文献
4.
N. V. Zubkova D. Yu. Pushcharovskii G. Giester E. Tillmanns I. V. Pekov O. D. Krotova 《Crystallography Reports》2004,49(6):964-968
The crystal structure of the mineral byelorussite-(Ce) NaMnBa2Ce2Ti2Si8O26(F,OH) · H2O belonging to the joaquinite group was solved and refined to R = 0.033 based on 4813 reflections with I > σ2(I). The parameters of the orthorhombic unit cell are a = 22.301(4) Å, b = 10.514(2) Å, c = 9.669(2) Å, V = 2267.1(8) Å3, sp. gr. Ama2, and Z = 4. The structure is composed of three-layer sheets, which consist of dimers of edge-sharing Ti octahedra located between isolated four-membered [Si4O2] rings. The sheets are linked to each other by Mn 5-vertex polyhedra to form a heteropolyhedral framework. Large cavities in the framework are occupied by Na 6-vertex polyhedra, Ba 11-vertex polyhedra, and REE 9-vertex polyhedra. 相似文献
5.
G. G. Sadikov A. S. Antsyshkina V. S. Sergienko A. L. Poznyak 《Crystallography Reports》2004,49(6):990-997
The crystal structure of the [Zn3(HEdta)2(H2O)6] complex (I) is determined by X-ray diffraction analysis. The crystals are orthorhombic, a = 14.780 Å, b = 29.699 Å, c = 7.032 Å, Z = 4, and space group Pna21. The structural units of crystals I are trinuclear linear molecules, in which the peripheral atoms Zn(1) and Zn(2) each coordinate two N atoms and three O atoms of the HEdta 3? ligand and the O(w) atom of the H2O molecule, whereas the central Zn(3) atom coordinates four O(w) atoms of the H2O molecules and two terminal O atoms of the two HEdta 3? ligands. The HEdta 3? ligand fulfills a hexadentate chelating—bridging function. The bond lengths are as follows: Zn-O(HEdta), 2.006(4)–2.123(4) Å; Zn-N, 2.214(6) and 2.128(5) Å; and Zn-O(w), 2.006(6)–2.225(5) Å. In structure I, there is a specific contact formed by hydrogen bonds, owing to which the distance between the central atoms of individual molecules appears to be shorter than that in covalently bonded complexes. 相似文献
6.
R. K. Rastsvetaeva I. V. Pekov N. V. Chukanov K. A. Rozenberg L. V. Olysych 《Crystallography Reports》2007,52(5):811-818
The high-sodium variety of cancrinite [Si6.3Al5.7O24][Na2(H2O)2][Na5.7(CO3)0.9(SO4)0.1(H2O)0.6] (Kovdor Massif, Kola Peninsula, Russia) and the calcium-containing variety of cancrisilite [Si6.6Al5.4O24][(Na1.2Ca0.4)(H2O)1.6][Na6(CO3)1.3(H2O)1.2] (Khibiny Massif, Kola Peninsula, Russia) are studied. The trigonal unit cell parameters of the crystal structures under investigation are as follows: a = 12.727(4) Å, c = 5.186(2) Å, and space group P3 for the former mineral and a = 12.607(4) Å, c = 5.111(1) Å, and space group P3 for the latter mineral. The reduced symmetry of the new varieties as compared to the symmetry of typical cancrinite and typical cancrisilite is associated with the specific features in the arrangement of the carbonate groups and water molecules in channels. This inference is confirmed by the IR spectroscopic data. 相似文献
7.
A. V. Barinova R. K. Rastsvetaeva N. V. Chukanov A. Pietraszko 《Crystallography Reports》2004,49(6):942-945
The crystal structure of Zn-containing greifensteinite from the Pirineus Mine (Minas Gerais, Brazil) was refined (R = 0.045, 562 reflections with |F| > 2σ(F)). The unit-cell parameters are a = 15.941(3) Å, b = 11.877(3) Å, c = 6.625(2) Å, β = 95.09(2)°; V = 1249.4 Å3; sp. gr. C2/c; and Z = 2. The idealized formula is [Mn(Fe2+, Zn)4]Ca2Be4(PO4)6(OH)4 · 6H2O. The mineral is isostructural with the previously studied monoclinic representatives of the roscherite group from different deposits and differs from these representatives in that it contains Zn in one of two octahedral positions. 相似文献
8.
A. G. Verevkin A. V. Vologzhanina L. B. Serezhkina V. N. Serezhkin 《Crystallography Reports》2010,55(4):602-608
The compound Rb2[(UO2)2(CrO4)3(H2O)2] · 4H2O was studied by X-ray diffraction. The crystals are monoclinic, a = 10.695(2) Å, b = 14.684(3) Å, c = 14.125(3) Å, β = 108.396(4)°, sp. gr. P21/c, Z = 4, V = 2104.9(7) Å3, and R = 0.0491. The main structural units are layers consisting of [(UO2)2(CrO4)3(H2O)2]2? anions belonging to the crystal-chemical group A 2 T 2 3 B 2M 2 1 (A = UL 2 2+ , T 3 and B 2 are CrO 4 2? , and M 1 is H2O) of uranyl complexes. The uranium-containing layered groups are held together by electrostatic interactions with rubidium cations, as well as by hydrogen bonds with the participation of inner- and outer-sphere water molecules. 相似文献
9.
E. V. Alekseev E. V. Suleimanov E. V. Chuprunov G. K. Fukin 《Crystallography Reports》2005,50(6):914-917
Single crystals of cobalt uranyl sulfate are grown. The crystal structure is established by X-ray diffraction: the orthorhombic system, sp. gr. Pmc21, a = 6.452(2) Å, b = 8.295(2) Å, c = 11.288(3) Å, R1 = 0.0303, wR2 = 0.0735 for reflections with I > 2σ(I). The structure of CoUO2(SO4)2 · 5H2O consists of infinite two-dimensional uncharged [CoUO2(SO4)2H2O]2∞ layers, which are linked to each other by hydrogen bonds. 相似文献
10.
The crystals of catena-dichloro-(dihydrogen pyrazine-2,6-dicarboxylato-O,O′,N,-N′) copper(II) dihydrate Cu[H2(2,6-PZDC)]Cl2?2H2O are monclinic, space group C2/c with a = 11.658(2) Å, b = 6.778(1) Å, c = 16.390(3) Å, β = 98.90(3)°, and Z = 4. Two adjacent copper(II) ions are bridged by a fully protonated pyrazine-2,6-dicarboxylic acid molecule which uses for bridging its O,O′,N-bonding moiety on one side and a single hetero-ring nitrogen atom on the other. Two chloride ions in axial position complete the octahedral coordination around the metal ions with bond distances: Cu–N 2.027(3) ÅA, Cu–N′ 2.005(3) ÅA, Cu–Cl. 2.281(1) ÅA, and Cu–O 2.446(2) ÅA. Copper(II) ions are located in the center of symmetry and are coplanar with the ligand acid molecule forming flat molecular chains propagating in the direction of the b axis. Hydrogen bonds via solvation water molecule link the chains into molecular layers parallel to the ac plane. Weak van der Waals type interactions operate between the layers. 相似文献
11.
The crystal structure of the mineral afwillite [Ca12(H2O)8][SiO4]4[SiO2(OH)2]4 from the northern Baikal region was refined in a triclinic unit cell with the following parameters: a = 16.330(2) Å, b = 5.6389(6) Å, c = 11.685(1) Å, α = 90.08(1)°, β = 126.446(2)°, γ = 89.95(1)°, and sp. gr. P1. The triclinic unit cell is related to the monoclinic unit cell determined earlier (sp. gr. Cc, a = 16.278(1) Å, b = 5.6321(4) Å, c = 13.236(1) Å, and β = 134.898(3)°) by the transformation matrix [?100/010/101]. The structural model was determined using the phase-correction procedure and refined anisotropically to R = 2.8% based on 3270 independent reflections with F > 3σ(F). The crystal-chemical formula of afwillite was revised. The characteristic features of the IR spectrum of afwillite were explained based on the structural data. 相似文献
12.
A. V. Oreshkina M. Kh. Rabadanov A. G. Ivanova G. Z. Kaziev 《Crystallography Reports》2007,52(6):1061-1065
Manganese(II) 9-molybdocobaltate(III) of the composition [Mn(H2O)4] · [CoMo9O27(OH)5] · 7H2O (I) has been synthesized for the first time and investigated using X-ray diffraction and thermal gravimetric analyses. Compound I crystallizes in the trigonal system with the following unit cell parameters: a = 15.926(1) Å, c = 12.363(1) Å, V = 2715.6(4) Å3, M = 1692.55, Z = 3, ρ(calcd) = 3.105 g/cm3, space group R32. 相似文献
13.
Compound Sr[cis(N)-Co(Ida)2]2 · 5H2O (I) is synthesized and its crystal structure is determined. The crystals are built of [Co(Ida)2]? anionic complexes, [Sr(H2O)3]2+ hydrated cations, and crystallization water molecules. Two independent anions are located on rotation axis 2 and have close structures. A distorted octahedral coordination of Co3+ atoms is formed by two N atoms and four O atoms of two Ida 2? ligands [Co-N, 1.932(3) and 1.940(3) Å; Co-O, 1.879–1.899(3) Å]. [Sr(H2O)3]2+ cations randomly occupy half of the positions in the vicinity of centers of inversion. In addition to three water molecules, the environment of the Sr2+ atom includes five O atoms of five Ida 2? ligands [Sr-O, 2.487(3)-2.889(5) Å]. Because of the disordering of [Sr(H2O)3]2+ cations, the structural function of the Ida 2- ligands varies from tridentate chelate to pentadentate bridging chelate. Sr-O and hydrogen bonds connect structural elements into a three-dimensional framework. The structure of I is compared with that of a related compound Sr[CoEdta]2·9H2O (II). It is shown that the formation of N-H…O hydrogen bonds, which connect [Co(Ida)2]? anionic complexes in I into compact chains, is an important factor leading to the difference between packings I and II. 相似文献
14.
R. K. Rastsvetaeva K. A. Rozenberg N. V. Chukanov S. M. Aksenov 《Crystallography Reports》2017,62(1):60-65
The crystal structure of ilyukhinite, a new mineral of the eudialyte group, is studied by X-ray diffraction. The mineral found in pegmatite bodies of the Kukisvumchorr Mountain (Khibiny alkaline complex) is characterized by low sodium content, high degree of hydration, and predominance of manganese over iron. The trigonal cell has the following parameters: a = 14.1695(6) and c = 31.026(1) Å; space group R3m. The structure is refined to final R = 0.046 in the anisotropic approximation of atomic displacements using 1527F > 3σF. The idealized formula of ilyukhinite (Z = 3) is written as (H3O,Na)14Ca6Mn2Zr3Si26O72(OH)2 · 3H2O. The new mineral differs from other representatives of the eudialyte group by the predominance of both oxonium in the N positions of extra-framework cations and manganese in the М2 position centering the tetragonal pyramid. 相似文献
15.
A. A. Grigor’eva N. V. Zubkova I. V. Pekov U. Kolitsch D. Yu. Pushcharovsky M. F. Vigasina G. Giester T. Dordević E. Tillmanns N. V. Chukanov 《Crystallography Reports》2011,56(5):832-841
Elpidite Na2ZrSi6O15 · 3H2O [space group Pbcm, a = 7.1312(12), b = 14.6853(12), and c = 14.6349(15) Å] from Khan Bogdo (Mongolia) and its K- and Rb-exchanged forms K1.78Na0.16H0.06ZrSi6O15 · 0.85H2O [Cmce, a = 14.054(3), b = 14.308(3), and c = 14.553(3) Å] and Na1.58Rb0.2H0.22ZrSi6O15 · 2.69H2O [Pbcm, a = 7.1280(10), b = 14.644(3), and c = 14.642(3) Å] that were obtained by cation exchange at 90°C, as well as K1.84Na0.11H0.05ZrSi6O15 · 0.91H2O [Cmce, a = 14.037(3), b = 14.226(3), and c = 14.552(3) Å] and Rb1.78Na0.06H0.16ZrSi6O15 · 0.90H2O [Cmce, a = 14.2999(12), b = 14.4408(15), and c = 14.7690(12) Å], obtained at 150°C are studied by single-crystal X-ray diffraction and IR spectroscopy. The base of the structures is a heteropolyhedral Zr-Si-O framework whose cavities accommodate Na (K, Rb) cations and H2O molecules. 相似文献
16.
A specimen of a new representative of the palygorskite-sepiolite family from Aris phonolite (Namibia) is studied by single-crystal X-ray diffraction. The parameters of the triclinic (pseudomonoclinic) unit cell are as follows: a = 5.2527(2) Å, b = 17.901(1) Å, c = 13.727(1) Å, α = 90.018(3)°, β = 97.278(4)°, and γ = 89.952(3)°. The structure is solved by the direct methods in space group P \(\bar 1\) and refined to R = 5.5% for 4168 |F| > 7σ(F) with consideration for twinning by the plane perpendicular to y (the ratio of the twin components is 0.52: 0.48). The crystal chemical formula (Z = 1) is (Na1.6K0.2Ca0.2)[Ca2(Fe 3.6 2+ Al1.6Mn0.8)(OH)9(H2O)2][(Fe 3.9 2+ Ti0.1)(OH)5(H2O)2][Si16O38(OH)2] · 6H2O, where the compositions of two ribbons of octahedra and a layer of Si tetrahedra are enclosed in brackets. A number of specific chemical, symmetrical, and structural features distinguish this mineral from other minerals of this family, in particular, from tuperssuatsiaite and kalifersite, which are iron-containing representatives with close unit cell parameters. 相似文献
17.
At room temperature, a new coordination polymer [Ni(tpt)(imi)3(H2O)]n was synthesized by the reaction of NiCl2?6H2O, terephthalic acid, and imidazole in aqueous solution. The structure was determined by X-ray crystallography. It crystallizes in monoclinicP21/n space group with the crystal cell parameters ofa = 9.8626(4) Å,b = 15.2498(3) Å, andc = 12.7681(3)Å, β = 90.309(2)°,V = 1920.33(10) Å3, andZ = 4. The crystal X-ray analysis shows that each nickel atom is coordinated by three imidazole ligands, two terephthalate ions, and one water molecule. Each terephthalate ion bridges two nickel atoms to form a zigzag chain. The chains are further linked together via hydrogen bonds to a three-dimensional network. 相似文献
18.
The crystal structure of mineral bussenite, Na2Ba2Fe[TiSi2O7][CO3]O(OH)(H2O)F, found in the Khibiny massif (the Kola Peninsula) has been determined. The parameters of the triclinic unit-cell are a = 5.399(3) Å, b = 7.016(9) Å, c = 16.254(14) Å, α = 102.44(8)°, β = 93.18(6)°, γ = 90.10(7)°, sp. gr. \(P\bar 1\), R = 0.054 for 1418 reflections with |F| > 2.5σ(F). The mineral studied belongs to the family of layered titanosilicates, in which, unlike the sulfate-and phosphate-containing representatives of this family, the interlayer spaces are filled with carbonate groups. 相似文献
19.
A. S. Antsyshkina G. G. Sadikov A. L. Poznyak V. S. Sergienko 《Crystallography Reports》2010,55(1):35-40
The crystal structure of Ca[Ni(HEdta)(H2O)]2 · 4H2O (HEdta 3?is a protonated anion of ethylenediaminetetraacetic acid) is determined. The unit-cell parameters are as follows: a = 7.706(1), b = 14.923(9), and c = 26.570(5) Å; V = 3055.6(2.4) Å3; Z = 8; and space group Pbcn. Crystals are shaped as tetragonal prisms and colored green, which is not characteristic of this class of compounds. The structure is built of Ca2+ cations, octahedral [Ni(HEdta)(H2O)]? complex anions, and crystallization water molecules. In the complex anion, one of the acetate branches is free of coordination, whereas the remaining three branches coordinate the central atom forming glycinate metallocycles. The structure is based on sandwich layers, which are formed by networks of flat tetragonal Ca[Ni(HEdta)(H2O)]4(H2O)2 fragments adjoining one another by vertices. 相似文献
20.
G. G. Sadikov T. V. Koksharova A. S. Antsyshkina I. S. Gritsenko V. S. Sergienko 《Crystallography Reports》2008,53(4):631-638
The copper(II) phthalate complex with nicotinamide [CuL 2(μ-Pht)(H2O)] · 0.5H2O(I) (where L is nicotinamide and Pht 2? is an anion of phthalic acid) is synthesized and investigated using IR spectroscopy and X-ray diffraction. The crystals of compound I are monoclinic, a = 13.368(2) Å, b = 7.891(3) Å, c = 20.480(2) Å, β = 108.69(2)°, Z = 4, and space group P21/c. The structural units of crystal I are linear chains formed by bridging phthalate anions and crystallization water molecules. The copper atom is coordinated by two pyridine nitrogen atoms of two nicotinamide ligands (Cu-N, 2.001 and 2.045 Å), two oxygen atoms of different phthalate anions (Cu-O, 1.964 and 2.235 Å), and the oxygen atom of the H2 O molecule (Cu-O, 2.014 Å). The coordination polyhedron of the copper atom is completed to an elongated (4 + 1 + 1) tetragonal bipyramid by the second (chelating) oxygen atom of the carboxyl group (Cu-O, 2.587 Å), which is one of the anions of phthalic acid. The linear polymer molecules are joined into complex macromolecular dimers with the closest internal contacts of the specific type. The macromolecular dimers are the main supramolecular ensembles of the crystal structure. 相似文献