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Abstract Hydroxylgugiaite, ideally (Ca 3 □ 1 ) Σ4 (Si 3.5 Be 2.5 ) Σ6 O 11 (OH) 3 , is a new mineral species from two localities in the Larvik plutonic complex in Porsgrunn, Telemark, Norway, and one locality in Ilimaussaq, Greenland. Hydroxylgugiaite crystals occur as squat dipyramids {111} (30 × 50 μm) or as elongate tetragonal prisms. The crystals are translucent, white to pale grey in color, with a white streak and vitreous luster. It is brittle, with no apparent cleavage. Hydroxylgugiaite is uniaxial positive with ω = 1.622 ± 0.002 and ϵ = 1.632 ± 0.002. There is no pleochroism and birefringence is low. The average of eight analyses of a single grain of type material (oxide wt.%) gave Na 2 O 2.04, CaO 32.90, FeO 0.22, MnO 0.74, BeO 13.47 (LA-ICP-MS), Al 2 O 3 0.74, SiO 2 44.06, F 1.74, H 2 O (assuming 3 OH + F) 4.93, Total (–0.73 O = F) 100.10. Potassium, strontium, and magnesium were measured but not detected. The calculated density is 2.79 g cm –3 . The empirical formula on the basis of 14 anions including 3 OH – + F – is: (Ca 2.76 Na 0.31 Mn 0.05 Fe 0.01 ) Σ3.13 (Si 3.45 Be 2.53 Al 0.07 ) Σ6.05 O 11 [(OH) 2.57 F 0.43 ] Σ3 . The formula from crystal-structure analysis of the Saga specimen is: (Ca 3.02 □ 0.98 ) Σ4 (Si 1.79 Be 0.21 ) Σ2 (Be 2.29 Si 1.71 ) Σ4 O 11 (OH) 3 . Combined structural and chemical data gives the following formula for the Nakkaalaaq specimen: (Ca 2.88 □ 0.98 Na 0.12 Mn 0.02 ) Σ4 (Si 1.80 Be 0.17 Al 0.03 ) Σ2 (Be 2.32 Si 1.68 ) Σ4 O 11 [(OH) 2.70 F 0.30 ] Σ3 ; with simplified formula (Ca,□) 4 (Si,Be) 2 (Be,Si) 4 O 11 (OH) 3 . The crystal structure of hydroxylgugiaite is tetragonal in acentric space group P 2 1 / m , with a 7.4151(2), b 7.4151, c 4.9652(1) A, V 272.9(1) A 3 , and Z = 1. It has been refined to an R index of 0.028 on the basis of 342 observed reflections and a correction for the {110} twin law. It is an H-bearing member of the melilite group. The structure has two distinct layers. The one crystallographically distinct Ca site with eight-fold coordination is a square antiprism polyhedron. The Ca polyhedra are in a layer with the H atoms. A second layer consists of corner-sharing Si/Be atoms in tetrahedral coordination with O. One H atom is bonded to an apical O atom that is not shared by two tetrahedra. This H atom is present only when there is a Ca -site vacancy. The other H atom is loosely bonded to the same O atom but at a different site. The IR spectrum supports this H-bonding scheme. Additional hydroxylgugiaite data is given for the other localities.

The title mol­ecule, C38H42N4O4, displays a helical structure induced by the combination of the C—C—C—C torsion angle [−10.8 (2)°] between two 2,3′-bipyridyl units attached to the 1,2-positions of the central benzene ring and consecutive connections between five aromatic rings through the meta- and ortho-positions. Intra­molecular C—H⋯π inter­actions between an H atom of a pyridine ring and the centroid of a another pyridine ring contributes to the stabilization of the helical structure. In the crystal, weak C—H⋯π inter­actions link the title mol­ecules into a two-dimensional supra­molecular network extending parallel to the ac plane, in which the mol­ecules with right- and left-handed helical structures are alternately arranged. Hirshfeld surface analysis and two-dimensional fingerprint plots indicate that the mol­ecular packing is dominated by van der Waals inter­actions between neighbouring H atoms, as well as by C—H⋯π inter­actions. One isopropoxyl group is disordered over two sets of sites [occupancy ratio 0.715 (5):0.285 (5)]. The title mol­ecule adopts a helical structure, in which two 2,3′-bipyridyl units are twisted up and down relative to the plane of the central benzene ring. Weak inter­molecular C—H⋯π inter­actions lead to formation of a two-dimensional supra­molecular network. Hirshfeld surface analysis indicates that the mol­ecular packing in the title compound is mainly dominated by inter­molecular H⋯H and H⋯C/C⋯H inter­actions.

This study examines two pegmatitic monazite samples (2a and 4b, these numbers are related to a previous study) to determine their crystal chemistry and effects of internal radiation damage using synchrotron high-resolution powder X-ray diffraction and electron-probe micro-analysis. Both the huttonite and cheralite substitutions are discussed. Rietveld structure refinement of sample 2a shows three different phases [2a = monazite-(Ce), 2b = monazite-(Ce), and 2c = xenotime-(Y)] with distinct structural parameters. The changes among the unit-cell parameters between the two monazite-(Ce) phases is more pronounced in the a followed by the b and c unit-cell parameters. Sample 4a is a single-phase monazite-(Sm) that contains 0.164 apfu Th. Phase 2c with space group I41/amd arises from redistribution of La, Ce, Pr, Nd, Sm, Gd, Dy, Si, and Y atoms from those in monazite (space group P21/n). A possible cause for the phase transition from monazite-(Ce) to xenotime-(Y) is α-radiation events over a long geological time. However, other chemical processes cannot be ruled out as a cause for the transition.

In the structure of the title salt, (C5H14N3)2[CuCl4], the CuII atom in the anion lies on a twofold rotation axis. The tetra­chlorido­cuprate(II) anion adopts a flattened tetra­hedral coordination environment and inter­acts electrostatically with the tetra­methyl­guanidinium cation. The crystal packing is additionally consolidated through N—H⋯Cl and C—H⋯Cl hydrogen bonds, resulting in a three-dimensional network structure. The crystal structure of bis­(tetra­methyl­guanidinium) tetra­chlorido­cuprate(II) contains distorted tetra­hedral [CuCl4]2− anions and tetra­methyl­guanidinium cations held together through N—H⋯Cl and C—H⋯Cl hydrogen bonds.

Abstract The newly developed GUMAP software creates element maps from OMDAQ list mode files, displays these maps individually or collectively, and facilitates on-screen definitions of specified regions from which a PIXE spectrum can be built. These include a free-hand region defined by moving the cursor. The regional charge is entered automatically into the spectrum file in a new GUPIXWIN-compatible format, enabling a GUPIXWIN analysis of the spectrum. The code defaults to the OMDAQ dead time treatment but also facilitates two other methods for dead time correction in sample regions with count rates different from the average.

Benzyl(4-methoxyphenyl)dithiophosphinic acid (HL) was obtained as solid and was treated with the NiCl(2)6H(2)O, CoCl(2)6H(2)O, ZnCl2, and CdCl2 to prepare its Ni(II), Co(II), Zn(II), and Cd(II) complexes. The nickel complex was further treated with pyridine which led to the formation of octahedral dipyridine derivative. HL was obtained through the addition reaction of the perthiophosphonic acid anhydride Lawesson reagent, (LR), [2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide], with the corresponding Grignard compound (benzylmagnesium bromide) in diethyl ether medium.The complexes were all of the stoichiometry of [M(L)(2)](x), with x = 1 for M = Ni2+ and x = 2 for M = Co2+, Cd2+ and Zn2+. The coordination geometry was square planar in the nickel(II) complex and tetrahedral in the others. Similar to many other nickel(II) complexes, the Ni(L)(2) reacts reversibly with pyridine to yield the octahedral complex ({(Py)(2)Ni(L)(2)}).The compounds were characterized by elemental analysis; MS, FTIR, and Raman spectroscopies. The magnetic susceptibilities of the complexes were measured to confirm the hybridization patterns and the geometries. Single-crystal X-ray analyses of Ni(L)(2) and [Co(L)(2)](2) complexes were also carried out to prove the molecular topologies. We are grateful for the financial assistance of Technical Research Council of Turkey (Grant No. TBAG 114Z091, TUBITAK). Technical Research Council of Turkey (TUBITAK) [TBAG 114Z091] WOS: 000368536500001

Crystals of the title compound, (C5H8N3)3[VO2(C2O4)2]·2.5H2O, a mononuclear VV complex, were obtained by slow evaporation at room temperature of an aqueous solution containing vanadium pentoxide, oxalic acid and 2,6-di­amino­pyridine. The asymmetric unit contains one bis­(oxalato)dioxovanadate(V) anionic complex, three 2,6-di­amino­pyridinium cations and two and a half uncoordinated water mol­ecules. The mononuclear vanadium(V) anions are connected to the organic cations and water mol­ecules through a strong N—H⋯O and O—H⋯O hydrogen-bond network, consolidated by π–π stacking inter­actions, to form a three-dimensional structure. The synthesis of complex compounds based on vanadium oxalates has grown considerably during the last decades, because of there biological and catalytic applications. This paper describes the synthesis and characterization of a new dioxovanadate(V) complex, (C5H8N3)3[VO2(C2O4)2]·2.5H2O.

In the title molecule, C13H13NO, the dihedral angle between phenyl and pyrrole rings is 57.2 (1)°. In the crystal, N—H...O hydrogen bonds link the molecules, forming chains propagating along thebaxis.

The structure of tetramethylammonium trifluoromethanesulfonate, C4H12N+·CF3SO3−, was determined at 110 K in the monoclinic space groupP21/m. The salt, which contains two cations and two anions in the asymmetric unit, has a network structure displaying C—H...O hydrogen bonding. Both the cation and the anion lie on special positions (mirror planes).

The title compound, [RhCl(C(21)H(21)P)(2)(CO)]·C(3)H(6)O, was precipitated in trace yield from a reaction of RhCl(cod)(THP) with P(p-tol)(3) in a 1:1 acetone-d(6)/CD(3)OD solution under a hydrogen atmosphere [p-tol = p-tolyl, THP = tris-(hydroxy-meth-yl)phosphine, P(CH(2)OH)(3), and cod = 1,5-cyclo-octa-diene]. The complex displays a square-planar geometry around the Rh(I) atom. The complex mol-ecules and the acetone mol-ecules are linked into a chain along the a axis by inter-molecular C-H⋯Cl and C-H⋯O hydrogen bonds.