Crystal structure reinvestigation and spectroscopic analysis of tricadmium orthophosphate
Ontology highlight
ABSTRACT:
SUBMITTER: Cherif F
PROVIDER: S-EPMC10833404 | biostudies-literature | 2023 Nov
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:The crystal structure of the title salt, ([H3NOH](+))3·[PO4](3-), consists of discrete hydroxyl-ammonium cations and ortho-phos-phate anions. The atoms of the cation occupy general positions, whereas the anion is located on a threefold rotation axis that runs through the phospho-rus atom and one of the phosphate O atoms. In the crystal structure, cations and anions are linked by inter-molecular O-H?O and N-H?O hydrogen bonds into a three-dimensional network. Altogether, one very strong O-H?O, two N-H?O hydrogen bonds of medium strength and two weaker bifurcated N-H?O inter-actions are observed.
| S-EPMC4645030 | biostudies-literature
Project description:The title compound, SrNi2Fe(PO4)3, synthesized by solid-state reaction, crystallizes in an ordered variant of the α-CrPO4 structure. In the asymmetric unit, two O atoms are in general positions, whereas all others atoms are in special positions of the space group Imma: the Sr cation and one P atom occupy the Wyckoff position 4e (mm2), Fe is on 4b (2/m), Ni and the other P atom are on 8g (2), one O atom is on 8h (m) and the other on 8i (m). The three-dimensional framework of the crystal structure is built up by [PO4] tetra-hedra, [FeO6] octa-hedra and [Ni2O10] dimers of edge-sharing octa-hedra, linked through common corners or edges. This structure comprises two types of layers stacked alternately along the [100] direction. The first layer is formed by edge-sharing octa-hedra ([Ni2O10] dimer) linked to [PO4] tetra-hedra via common edges while the second layer is built up from a strontium row followed by infinite chains of alternating [PO4] tetra-hedra and FeO6 octa-hedra sharing apices. The layers are held together through vertices of [PO4] tetra-hedra and [FeO6] octa-hedra, leading to the appearance of two types of tunnels parallel to the a- and b-axis directions in which the Sr cations are located. Each Sr cation is surrounded by eight O atoms.
| S-EPMC4647370 | biostudies-literature
Project description:The crystal structure of the mineral lautite (copper arsenic sulfide), CuAsS, previously described as either centrosymmetric [Pnma; Marumo & Nowacki (1964 ?). Schweiz. Miner. Petro. Mitt.44, 439-454] or noncentrosymmetric [Pna2(1); Craig & Stephenson (1965 ?). Acta Cryst.19, 543-547], was reinvestigated by means of single-crystal X-ray diffraction. The centrosymmetric structural model reported previously was confirmed, although with improved precision for the atomic coordinates and inter-atomic distances. Lautite shows a sphalerite-derivative structure with a linking of Cu[AsS(3)], As[CuAs(2)S] and S[Cu(3)As] tetra-hedra. All atoms lie on special positions (Wyckoff position 4c, site symmetry m).
| S-EPMC2960788 | biostudies-literature
Project description:A crystal structure reinvestigation of AgF based on a low-temperature high-resolution single-crystal X-ray diffraction data is reported. Silver(I) fluoride crystallizes in the rock salt structure type (Fm m) with a unit-cell parameter of 4.92171 (14) Å at 100 K, resulting in an Ag-F bond length of 2.46085 (7) Å.
| S-EPMC9912324 | biostudies-literature
Project description:The structure of Li(3)V(2)(PO(4))(3) has been reinvestigated from single-crystal X-ray data. Although the results of the previous studies (all based on powder diffraction data) are comparable with our redetermination, all atoms were refined with anisotropic displacement parameters in the current study, and the resulting bond lengths are more accurate than those determined from powder diffraction data. The title compound adopts the Li(3)Fe(2)(PO(4))(3) structure type. The structure is composed of VO(6) octa-hedra and PO(4) tetra-hedra by sharing O atoms to form the three-dimensional anionic framework (∞) (3)[V(2)(PO(4))(3)](3-). The positions of the Li(+) ions in the empty channels can vary depending on the synthetic conditions. Bond-valence-sum calculations showed structures that are similar to the results of the present study seem to be more stable compared with others. The classical charge balance of the title compound can be represented as [Li(+)](3)[V(3+)](2)[P(5+)](3)[O(2-)](12).
| S-EPMC3569174 | biostudies-literature
Project description:Crystals of the new compound, AgSr4Cu4.5(PO4)6, were grown successfully by the hydrothermal process. The asymmetric unit of the crystal structure of the title compound contains 40 independent atoms (4 Sr, 4.5 Cu, 1 Ag, 6 P and 24 O), which are all in general positions except for one Cu atom, which is located on an inversion centre. The Cu atoms are arranged in CuOn (n = 4 or 5) polyhedra, linked through common oxygen corners to build a rigid three-dimensional motif. The connection of these copper units is assured by PO4 tetrahedra. This arrangement allows the construction of layers extending parallel to the (100) plane and hosts suitable cavities in which Ag+ and Sr2+ cations are located. The crystal-structure cohesion is ensured by ionic bonds between the silver and strontium cations and the oxygen anions belonging to two adjacent sheets. Charge-distribution analysis and bond-valence-sum calculations were used to validate the structural model.
| S-EPMC7001842 | biostudies-literature
Project description:Single crystals of magnesium copper(II) bis-[orthophosphate(V)] monohydrate, Mg1.65Cu1.35(PO4)2·H2O, were grown under hydro-thermal conditions. The crystal structure is formed by three types of cationic sites and by two unique (PO4)(3-) anions. One site is occupied by Cu(2+), the second site by Mg(2+)and the third site by a mixture of the two cations with an Mg(2+):Cu(2+) occupancy ratio of 0.657 (3):0.343 (3). The structure is built up from more or less distorted [MgO6] and [(Mg/Cu)O5(H2O)] octa-hedra, [CuO5] square-pyramids and regular PO4 tetra-hedra, leading to a framework structure. Within this framework, two types of layers parallel to (-101) can be distinguished. The first layer is formed by [Cu2O8] dimers linked to PO4 tetra-hedra via common edges. The second, more corrugated layer results from the linkage between [(Cu/Mg)2O8(H2O)2] dimers and [MgO6] octa-hedra by common edges. The PO4 units link the two types of layers, leaving space for channels parallel [101], into which the H atoms of the water mol-ecules protrude. The latter are involved in O-H⋯O hydrogen-bonding inter-actions (one bifurcated) with framework O atoms across the channels.
| S-EPMC4331867 | biostudies-literature
Project description:The title compound, SrCo2Fe(PO4)3, has been synthesized by a solid-state reaction. It crystallizes with the α-CrPO4 type structure. In this structure, all atoms are on special positions of the Imma space group, except for two O atoms which are located on general positions. The three-dimensional network in the crystal structure is made up of two types of layers stacked normal to (100). The first layer is built from two edge-sharing CoO6 octa-hedra, leading to the formation of Co2O10 dimers that are connected to two PO4 tetra-hedra by a common edge and corners. The second layer results from apex-sharing FeO6 octa-hedra and PO4 tetra-hedra, which form linear chains alternating with a zigzag chain of Sr(II) cations. These layers are linked together by common vertices of PO4 tetra-hedra and FeO6 octa-hedra to form an open three-dimensional framework that delimits two types of channels parallel to [100] and [010] where the Sr(II) cations are located. Each Sr(II) cation is surrounded by eight O atoms.
| S-EPMC4971858 | biostudies-literature
Project description:Semiconducting indium sulfide (In2S3) has recently attracted considerable attention as a buffer material in the field of thin film photovoltaics. Compared with this growing interest, however, detailed characterizations of the crystal structure of this material are rather scarce and controversial. In order to close this gap, we have carried out a reinvestigation of the crystal structure of this material with an in situ X-ray diffraction study as a function of temperature using monochromatic synchrotron radiation. For the purpose of this study, high quality polycrystalline In2S3 material with nominally stoichiometric composition was synthesized at high temperatures. We found three modifications of In2S3 in the temperature range between 300 and 1300?K, with structural phase transitions at temperatures of 717?K and above 1049?K. By Rietveld refinement we extracted the crystal structure data and the temperature coefficients of the lattice constants for all three phases, including a high-temperature trigonal ?-In2S3 modification.
| S-EPMC4886618 | biostudies-literature
Project description:The title compound, Na2Co2Fe(PO4)3, was synthesized by a solid-state reaction. This new stoichiometric phase crystallizes in an alluaudite-like structure. In this structure, all atoms are in general positions except for four atoms which are located at the special positions of the C2/c space group. One Co atom, one P and one Na atom are all located on Wyckoff position 4e (2), while the second Na atom is located on an inversion centre 4a (-1). The other Co and Fe atoms occupy a general position with a statistical distribution. The open framework results from [(Co,Fe)2O10] units of edge-sharing [(Co,Fe)O6] octa-hedra, which alternate with [CoO6] octa-hedra that form infinite chains running along the [10-1] direction. These chains are linked together through PO4 tetra-hedra by the sharing of vertices so as to build layers perpendicular to [010]. The three-dimensional framework is accomplished by the stacking of these layers, leading to the formation of two types of tunnels parallel to [010] in which the Na(+) cations are located, each cation being surrounded by eight O atoms.
| S-EPMC4420128 | biostudies-other