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Co-precipitation of mineral-based salts during scaling remains poorly understood and thermodynamically undefined within the water industry. This study focuses on investigating calcium carbonate and calcium sulfate mixed precipitation in scaling. Scaling is often observed in the produced water supply as a result of treatment processes. Co-precipitation results were compared with experimental results of a single salt crystallization. Several parameters were carefully monitored, including the electrical conductivity, pH value, crystal morphology and crystal form. The existence of the calcium carbonate scale in the mixed system encourages the loose calcium sulfate scale to become more tightly packed. The mixed scale was firmly adhered to the beaker, and the adhesion of the co-deposition product was located between the pure calcium sulfate scale and the pure calcium carbonate scale. The crystalline form of calcium sulfate was gypsum in both pure material deposition and mixed deposition, while the calcium carbonate scale was stable in calcite form in the pure material deposition. In the co-deposition, apart from calcite form, some calcium carbonate scale crystals had metastable vaterite form. This indicated that the presence of SO42− ions reduced the energy barrier of the calcium carbonate scale and hindered its transformation from a vaterite form to a calcite one, and the increase in HCO3− content inhibited the formation of calcium sulfate scale.

C22H28Mn2N8O6, triclinic, P1̅ (no. 2), a = 7.2827(15) Å, b = 8.6433(17) Å, c = 11.410(2) Å, α = 98.58(3)°, β = 96.15(3)°, γ = 107.67(3)°, V = 667.8(2) Å3, Z = 1, Rgt(F) = 0.0414, wRref(F2) = 0.0972, T = 293(2) K.

Through hydrothermal treatment, a series of new 3D noninterpenetrating cobalt(iii)-lanthanide(iii) heterometallic coordination assemblies bearing 2,2′-bipyridine-4,4′-dicarboxylate (H2bpdc) ligands, CoLn2(bpdc)3(NO3)3(H2O)6·3.5H2O (Ln = Gd (2), Eu (3), Sm (4), La (5)), have been obtained which may be regarded as being derived from Co2(Hbpdc)2(bpdc)2(H2O)2·2H2O (1) with one-dimensional (1D) zigzag chains. The results of single-crystal X-ray analysis and the X-ray photoelectron spectroscopy study show that each Co center in all of the compounds is located in six-coordinate octahedral surroundings, and exhibits the trivalent oxidation state. Compounds 2–5possess isostructural 3D NaCl-type frameworks containing Ln2O16building blocks, exhibiting square pores with dimensions of ca.8 × 8 Å2along the [010] direction, which are occupied by nitrate anions and non-coordinated water molecules. The frameworks of 2–5are stable up to ca.300 °C followed by removal of the coordinated and uncoordinated water molecules, as is evident from the associated weight loss. The magnetic and gas adsorption properties for the Co(iii)-Gd(iii) system have been investigated. [ABSTRACT FROM AUTHOR]

The article describes the crystal structure of 5-(4,5-ethylenedithio-1,3-dithiol-2-yl-idene)-1,3,4,6-tetrathiapentalen-2-one (EDTO-TTP) and 5-[4,5-(ethene-1,2-diyldithio)-1,3-dithiol-2-ylidene]-1,3,4,6-tetrathiapentalen-2-one (VDTO-TTP). It shows the planar conformation adopted by EDTO-TTP molecule as well as the similarity of the bond characteristics of both compounds. Also reported is the intermolecular interactions exhibited by the EDTO-TTP crystal structure, including transverse and longitudinal interactions, and hydrogen bonding.

The title polymeric compound, {[MnHg(SCN)4(H2O)]-C4H8O2S}n, consists of slightly distorted MnN4O2 octahedra and HgS4 tetrahedra. Each MnII ion is bound to N atoms belonging to the thiocyanate (SCN) groups and to two O atoms of adjacent water ligands. The sulfolane molecule connects with the coordinated water molecule through hydrogen bonding. Each HgII atom is coordinated by four SCN S atoms. The two adjacent MnII atoms and two O atoms of bridging water molecules connect with one another and form a parallelogram. Each pair of MnII and HgII atoms is connected by an -SCN- bridge, forming an infinite three-dimensional structure. [ABSTRACT FROM AUTHOR]

In the title compound, C7H11O3PS4, the five-membered ring is in an envelope conformation. The average values of the S—C sp3 and S—C sp2 bond lengths are 1.813 (6) and 1.755 (8) Å, respectively. The crystal packing is stabilized by weak inter­molecular C—H⋯O hydrogen bonds. [ABSTRACT FROM AUTHOR]

Focuses on the study conducted by Chinese scientists on determining the structure of rubidium gadolinium bis(tungstate). Composition of the crystal with corner- and edge-sharing WO₆ octahedral and GdO₈ polyhedral groups; Significance of the WO₆ octahedral and GdO₈ polyhedral groups in giving rise to a Gd-WO₄ polyhedral backbone surrounding structural cavities filled with rubidium cations; Significance of the structure of the Gd and Rb atoms in the twofold axes.

In the title complex, [Cd(SCN)2(C4H8O2S)2] n, the CdII atom, on an inversion centre, is within a distorted N2S2O2 octahedron and the five-membered ring has a distorted envelope conformation. In the crystal structure, neighbouring Cd atoms are connected by –SCN– bridges, leading to the formation of an infinite three-dimensional –Cd–NCS–Cd– network. [ABSTRACT FROM AUTHOR]

The crystal structure of a new bimetallic seleno­cyanate, zinc cadmium seleno­cyanate or poly[tetra-μ2-seleno­cyanato-cadmium(II)zinc(II)], [ZnCd(SeCN)4] n, is an infinite three-dimensional network in which the slightly distorted CdSe4 and ZnN4 tetra­hedra are connected by –SeCN– bridges. The whole structure can be viewed as a diamondoid network with Cd and Zn nodes and –SeCN– spacers. [ABSTRACT FROM AUTHOR]

In the title complex, (C6H8N)2[Zn(dmit)2] (dmit is 2-thioxo-1,3-dithiole-4,5-dithiol­ate, C3S5), each Zn atom is coordinated by four dmit S atoms that define a distorted tetra­hedral arrangement. The crystal structure is stabilized by C—H⋯S hydrogen bonding and S⋯S contacts. [ABSTRACT FROM AUTHOR]

The title compound, C13H6O4S5, possesses crystallographically imposed mirror symmetry, with the atoms of the C=S group lying on the mirror plane. It is an example of the general formula [ RCO]2(dmit), where R is a furan ring and dmit is 2-thioxo-1,3-dithiole-4,5-dithiol­ate. The components exhibit some polarization of their mol­ecular–electronic structure. The dmit and furan moieties exhibit a high degree of conjugation, as the introduction of C=O connecting the conjugated furan (donor) and dmit (acceptor) rings forms a good conjugated system with high delocalization. A polar three-dimensional framework is built from a combination of inter­molecular contacts, namely S⋯S inter­actions and C—H⋯O hydrogen bonding. The structural characteristics lead to good second-order non-linear optical properties. [ABSTRACT FROM AUTHOR]

The title complex, [Zn(C2H8N2)3][Ni(C4N2S2)2], contains a [Zn(C2H8N2)3]2+ complex cation with a distorted octahedral coordination of the Zn atom and an [Ni(C4N2S2)2]2− anion with a slightly distorted square-planar geometry for the NiII atom. The cation occupies a special position on a twofold axis, whereas the anion lies about a crystallographic inversion centre. [ABSTRACT FROM AUTHOR]

The title complex, [Zn(C2H8N2)3][Zn(C4N2S2)2], exists as discrete ions, both of which lie on twofold rotation axes. The [Zn(C2H8N2)3]2+ cation exhibits a slightly distorted octahedral geometry. In the [Zn(C4N2S2)2]2− anion, the ZnII atom is surrounded by two chelating ligands in a distorted tetrahedral geometry. The crystal structure is stabilized by hydrogen bonds of the types N—H⋯N and N—H⋯S. [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound, C26H21NO3·0.25H2O, reveals one stereogenic centre in the molecule. Nevertheless, due to the observed centrosymmetric space group, both enantiomers are present in the crystal packing. The water molecule of crystallisation is located on a crystallographic inversion center. The molecule contains one five-membered ring (A) and three six-membered rings (benzyl ring B, benzylidene ring C and formylbenzyl ring D). All four rings are not coplanar: the dihedral angles between rings A and B, A and C, and A and D are 70.35 (9), 33.8 (1) and 60.30 (9)°, respectively. In the crystal, pairs of weak C—H...O interactions lead to the formation of centrosymmetric dimers. Additional C—H...O interactions link the dimers into chains along [011].

The complete molecule of the title compound, C28H28B2Br4O4, is generated by the application of a centre of inversion. In the molecule, the BO2 plane is perpendicular to that through the pyrene ring [dihedral angle = 86.27 (13)°]. In the crystal, molecules stack into columns along the b axis, the closest contact between these being of the type C—Br...π.

In the crystal structure of the title compound, C21H17NO3, the dibenzo–isoquinoline–dione unit has a planar structure, the maximum atomic deviation being 0.091 (3) Å. The crystal structure is stabilized by π–π stacking [centroid–centroid distance = 3.851 (2) Å] and intermolecular N—H...O hydrogen bonding.

The asymmetric unit of the title compound, C23H12O4, contains two nearly parallel independent molecules; the dihedral angles between the phenanthrene ring systems of the two molecules and between the benzene rings of the two molecules are 4.97 (9) and 8.1 (2)°, respectively. In each molecule, the benzene ring is nearly perpendicular to the phenanthrene ring system, with dihedral angles of 86.42 (19) and 86.68 (18)°. π–π stacking exists between the phenanthrene ring systems of the two independent molecules [centroid–centroid distance = 3.698 (2) Å]. Short intermolecular contacts [O...O = 2.86 (2) and C...O = 2.88 (2) Å] are also present in the crystal structure.

In the title molecule, C34H53BrO4, all the cyclohexane rings adopt chair conformations, while the cyclopentane ring adopts an envelope conformation. In the crystal, weak intermolecular C—H...O hydrogen bonds link the molecules into corrugated sheets parallel to the ab plane.

In the title compound, C31H27N3, the cyclohexene ring has an envelope configuration. In the crystal structure, there is an 34 Å3 void around the inversion center, but the low electron density (0.13 e Å−3) in the difference Fourier map suggests no solvent molecule occupying this void. No hydrogen bonding is found in the crystal structure.

In the title compound, C15H18ClNO2, the amide group is coplanar with the chlorophenyl group, making a dihedral angle of 1.71 (12)°. The cyclopentanone ring adopts a twist conformation. A weak intramolecular C—H...O hydrogen bond is observed. Molecules are linked into cyclic centrosymmetric dimers by paired N—H...O hydrogen bonds.

The title compound, C20H19NO, is a substructure of CP-640186, a potent inhibitor of mammalian acetyl-coenzyme A carboxylases. In the crystal structure, the amide group forms a dihedral angle of 87.0 (1)° with the plane of the anthracene unit and the piperidine ring adopts a chair conformation. Molecules are arranged into layers parallel to (100) and adjacent anthracene units within layers form dihedral angles of 13.2 (1)°. C—H...O interactions from the piperidine rings to the C=O group of the amide are observed between layers.

The title compound, [Ni(C5O5)(C10H8N2)2], lies across a crystallographic twofold axis, around which two 2,2′-bipyridine (2,2′-bipy) ligands are arranged in a propeller manner. The local geometry of the NiN4O2 coordination core basically adopts an octahedral geometry. The molecular twofold axis is along the direction of the molecular dipole moment, and the complex is packed with its dipole moment alternately along the +b and −b directions. The crystal structure is stabilized by intermolecular C—H...O hydrogen bonds.

The crystal structure of the title compound, Na+·C3H2N3O3−·H2O, contains double chains of edge-shared distorted NaO6 octahedra propagating in the [100] direction. The double chains are linked by the isocyanurate anions. [ABSTRACT FROM AUTHOR]

By combining a new, large π-conjugated bidentate ligand, 2,8-bis[2-(2-pyridyl)vinyl]-5,11-di(2-ethylhexyl)-indolo[3,2-b]carbazole (BPVIC) with a [Cd(NCS) 2] ∞polymer chain, a novel supramolecular coordination polymer, [Cd 2(BPVIC) 2(SCN) 4] ∞, with network structure has been prepared. The crystal structures of the ligand and the coordination polymer were determined by X-ray crystallography. The crystallographic analyses revealed that “drums” formed by the ligands, Cd 2+cations, and SCN −anions are interconnected, leading to the formation of infinite three-dimensional networks. The π−π and C−H···π interactions among the free ligands, acting as energy traps and increasing nonradiative decay, are eliminated effectively in the metal coordination polymer. The metal coordination polymer exhibits strong luminescence in the yellow region and therefore is a potential luminescent material. [ABSTRACT FROM AUTHOR]

The molecules of the title compound, C11H13N3O3, are linked by O—H⋯N and N—H⋯O interactions into a linear hydrogen-bonded chain. [ABSTRACT FROM AUTHOR]

The title compound (alternative name dimethyl croconate), C7H6O5, is the first example of a croconate ether. The mol­ecule is essentially planar and exhibits a local symmetry ( C2 v) that is different from that shown by the croconate dianion ( C5 h), indicating that the geometry of these compounds is very sensitive to the electric charge state. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, C23H19NO2, the mol­ecular backbone is nearly planar, with a dihedral angle of 11.58 (12)° between the planes of the carbazole and benzene groups. [ABSTRACT FROM AUTHOR]

In the title compound, C13H10ClN3, the benzimidazole and chloropyridyl groups are planar and make a dihedral angle of 68.01 (18)°. There are two weak C—H⋯N hydrogen bonds, producing sheets parallel to (100). [ABSTRACT FROM AUTHOR]