scholarly journals Tris(cis-2-hydroxycyclohexane-1,3,5-triaminium) hydrogen sulfate octachloride dihydrate

2012 ◽  
Vol 68 (6) ◽  
pp. o1899-o1900
Author(s):  
Christian Neis ◽  
Günter J. Merten ◽  
Kaspar Hegetschweiler

The 2-hydroxycyclohexane-1,3,5-triaminium (= H3 L 3+) cation of the title compound, 3C6H18N3O3+·8Cl−·HSO4 −·2H2O, exhibits a cyclohexane chair with three equatorial ammonium groups and one axial hydroxy group in an all-cis configuration. The hydrogen sulfate anion and two water molecules lie on or in proximity to a threefold axis and are disordered. The crystal structure features N—H...Cl and O—H...Cl hydrogen bonds. Three C 3-symmetric motifs can be identified in the structure: (i) Two chloride ions (on the C 3-axis) together with three H3 L 3+ cations constitute an [(H3 L)3Cl2]7+ cage. (ii) The lipophilic C6H6-sides of three H3 L 3+ cations, which are oriented directly towards the C 3-axis, generate a lipophilic void. The void is filled with the disordered water molecules and with the disordered part of the hydrogen sulfate ion. The hydrogen atoms of these disordered moieties were not located. (iii) Three H3 L 3+ cations together with one HSO4 − and three Cl− counter-ions form an [(HSO4)(H3 L)3Cl3]5+ cage. Looking along the C 3-axis, these three motifs are arranged in the order (cage 1)...(lipophilic void)...(cage 2). The crystal studied was found to be a racemic twin.

1975 ◽  
Vol 53 (15) ◽  
pp. 2345-2350 ◽  
Author(s):  
Monique Authier-Martin ◽  
André L. Beauchamp

The title compound belongs to space group P21/c with a = 23.99(1), b = 4.245(2), c = 25.98(1) Å, β = 117.58(7)°, and Z = 8. The structure was solved by the heavy-atom method and refined by block-diagonal least squares on 2589 independent observed reflections. All non-hydrogen atoms were refined anisotropically and some of the hydrogen atoms were located but their parameters were not refined. The final values of R and Rw were 0.042 and 0.047, respectively.The two nonequivalent mercury atoms have very similar environments. Two short Hg—Cl bonds (2.34–2.38 Å) at ∼ 165° define a quasi-molecular HgCl2 unit. Overall octahedral coordination is completed with two chloride ions at 2.76–2.84 Å and two chlorine atoms at 3.19–3.26 Å on neighboring HgCl2 quasi-molecules. HgCl6 octahedra share edges to form twofold ribbons in the b direction. This pattern of octahedra is identical with the onereported for β-NH4HgCl3. The cations are pairs of N(1)-protonated adenine molecules linked by two N(10)—H(10)… N(7) hydrogen bonds and stacked in the b direction. Water molecules act as acceptors in moderately strong hydrogen bonds with acidic protons H(1) and H(9) of adeninium ions. Other generally weaker hydrogen bonds exist between the various parts of the structure.


2015 ◽  
Vol 71 (12) ◽  
pp. 1444-1446 ◽  
Author(s):  
Tamara J. Lukianova ◽  
Vasyl Kinzhybalo ◽  
Adam Pietraszko

In the title molecular salt, 3C5H12N+·HSO4−·SO42−, each cation adopts a chair conformation. In the crystal, the hydrogen sulfate ion is connected to the sulfate ion by a strong O—H...O hydrogen bond. The packing also features a number of N—H...O hydrogen bonds, which lead to a three-dimensional network structure. The hydrogen sulfate anion accepts four hydrogen bonds from two cations, whereas the sulfate ion, as an acceptor, binds to five separate piperidinium cations, forming seven hydrogen bonds.


Author(s):  
H. R. Rajegowda ◽  
P. A. Suchetan ◽  
R. J. Butcher ◽  
P. Raghavendra Kumar

A hydrogen sulfate salt, C15H18NSe+·HSO4 −·H2O or [BnSeCH2CH(Ph)NH3 +](HSO4 −), of a chiral selenated amine (R)-2-(benzylselanyl)-1-phenylethanamine (BnSeCH2CH(Ph)NH2) has been synthesized and characterized by elemental analysis,1H and 13C{1H} NMR, FT–IR analysis, and single-crystal X-ray diffraction studies. The title salt crystallizes in the monohydrate form in the non-centrosymmetric monoclinic P21 space group. The cation is somewhat W shaped with the dihedral angle between the two aromatic rings being 60.9 (4)°. The carbon atom attached to the amine nitrogen atom is chiral and in the R configuration, and, the –C—C– bond of the –CH2—CH– fragment has a staggered conformation. In the crystal structure, two HSO4 − anions and two water molecules form an R 4 4(12) tetrameric type of assembly comprised of alternating HSO4 − anions and water molecules via discrete D(2) O—H...O hydrogen bonds. This tetrameric assembly aggregates along the b-axis direction as an infinite one-dimensional tape. Adjacent tapes are interconnected via discrete D(2) N—H...O hydrogen bonds between the three amino hydrogen atoms of the cation sandwiched between the two tapes and the three HSO4 − anions of the nearest asymmetric units, resulting in a complex two-dimensional sheet along the ab plane. The pendant arrangement of the cations is stabilized by C—H...π interactions between adjacent cations running as chains down the [010] axis. Secondary Se...O [3.1474 (4) Å] interactions are also observed in the crystal structure. A Hirshfeld surface analysis, including d norm, shape-index and fingerprint plots of the cation, anion and solvent molecule, was carried out to confirm the presence of various interactions in the crystal structure.


2005 ◽  
Vol 69 (1) ◽  
pp. 77-88 ◽  
Author(s):  
T. Echigo ◽  
M. Kimata ◽  
A. Kyono ◽  
M. Shimizu ◽  
T. Hatta

AbstractThe crystal structure of whewellite [Ca(C2O4)·H2O] and the dehydration mechanism of caoxite [Ca(C2O4)·3H2O] have been studied by means of differential thermal analysis, X-ray diffraction (powder and single-crystal) analysis and infrared analysis. The first and second analyses confirmed the direct transformation of caoxite into whewellite without an intermediate weddellite [Ca(C2O4)·2H2O] stage. Infrared spectra obtained from caoxite, weddellite and whewellite emphasize the similarity of the O–H-stretching band and O–C–O-stretching band in whewellite and caoxite and the unique bands of weddellite. The structure refinement at low temperature (123 K) reveals that all the hydrogen atoms of whewellite form hydrogen bonds and the two water molecules prop up the crystal structure by the hydrogen bonds that cause a strong anisotropy of the displacement parameter.Comparing the structural features of whewellite with those of weddellite and caoxite suggests that caoxite and whewellite have a sheet structure consisting of Ca2+ ions and oxalate ions although weddellite does not. It is additionally confirmed that the sheets of caoxite are corrugated by hydrogen bonds but whewellite has flat sheets. The corrugated sheets of caoxite would be flattened by dehydration so the direct transformation of caoxite into whewellite would not occur via weddellite. Essential for this transformation is the dehydration of interlayered water molecules in caoxite leading to the building of the crystal structure of whewellite on its intralayered water molecules. The difference in conformation of water molecules between those two crystal structures may explain the more common occurrence of whewellite than of caoxite in nature.


Author(s):  
Avijit Kumar Paul

In the title compound, [Zn(C4H11N2)2(S2O3)2]·2H2O, two thiosulfate ions coordinate to the zinc(II) atom through the terminal S atoms. The tetrahedral coordination around the ZnII ion is completed by ligating to two N atoms of two piperazinium ions. The remaining two N atoms of the piperazinium ions are diprotonated and do not coordinate to the metal centre. In the crystal, however, they are involved in N—H...Owater and N—H...Osulfato hydrogen bonds. Together, a series of N—H...O and O—H...O hydrogen bonds, involving the O atoms of the thiosulfate ions and the water molecules as acceptors and the hydrogen atoms of the piperazinium ions and the water molecules as donors, form a three-dimensional supramolecuar structure. Within this framework there are a number of intra- and intermolecular C—H...O and C—H...S contacts present.


Author(s):  
Naheed Bibi ◽  
Renan Barrach Guerra ◽  
Luis Enrique Santa Cruz Huamaní ◽  
André Luiz Barboza Formiga

The crystal structure of the title compound, [Ru(C7H6N4)3](PF6)2·3H2O, a novel RuII complex with the bidentate ligand 2-(1H-imidazol-2-yl)pyrimidine, comprises a complex cation in the meridional form exclusively, with a distorted octahedral geometry about the ruthenium(II) cation. The Ru—N bonds involving imidazole N atoms are comparatively shorter than the Ru—N bonds from pyrimidine because of the stronger basicity of the imidazole moiety. The three-dimensional hydrogen-bonded network involves all species in the lattice with water molecules interacting with both counter-ions and NH hydrogen atoms from the complex. The supramolecular structure of the crystal also shows that two units of the complex bind strongly through a mutual N—H...N bond. The electronic absorption spectrum of the complex displays an asymmetric band at 421 nm, which might point to the presence of two metal-to-ligand charge-transfer (MLCT) bands. Electrochemical measurements show a quasi-reversible peak referring to the RuIII/RuII reduction at 0.87 V versus Ag/AgCl.


Author(s):  
Carlos L. Santana ◽  
Eric W. Reinheimer ◽  
Ryan H. Groeneman

The formation and crystal structure of a hydrated molecular salt that results in a square network is reported. The crystalline solid is based upon the tetraprotonated photoproduct rtct-tetrakis(pyridin-4-yl)cyclobutane (4H- rtct -TPCB)4+ along with two sulfate anions (SO4 2−) and eight waters of hydration, namely, 4,4′,4′′,4′′′-(cyclobutane-1,2,3,4-tetrayl)tetrapyridinium bis(sulfate) octahydrate, C24H24N4 4+·2SO4 2−·8H2O. The fully protonated photoproduct acts as a four-connecting node within the square network by engaging in four charge-assisted N+—H...O hydrogen bonds to the sulfate anion. The observed hydrogen-bonding pattern in this square network is akin to T-silica, which is a metastable form of SiO2. The included water molecules and sulfate anions engage in numerous O—H...O hydrogen bonds to form various hydrogen-bonded ring structures.


2020 ◽  
Vol 35 (1) ◽  
pp. 53-60
Author(s):  
Diana Gonzalez ◽  
Joseph T. Golab ◽  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton

The crystal structure of pantoprazole sodium sesquihydrate has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Pantoprazole sodium sesquihydrate crystallizes in space group Pbca (#61) with a = 33.4862(6), b = 17.29311(10), c = 13.55953(10) Å, V = 7852.06(14) Å3, and Z = 16. The crystal structure is characterized by layers parallel to the bc-plane. One layer contains the Na coordination spheres. The two independent sodium ions are trigonal bipyramidal and octahedral. The NaO3N2 and NaO4N2 coordination spheres share an edge to form pairs. The sodium bond valence sums are 1.17 and 1.15. The difluoromethyl groups are probably disordered. Two water molecules act as hydrogen bond donors to pyridine nitrogen atoms and sulfoxide oxygen atoms. The third water molecule participates in bifurcated hydrogen bonds, but one of its hydrogen atoms does not participate in hydrogen bonds. The powder pattern is included in the Powder Diffraction File™ as entry 00-065-1424.


2007 ◽  
Vol 72 (6) ◽  
pp. 545-554 ◽  
Author(s):  
Goran Bogdanovic ◽  
Nada Bosnjakovic-Pavlovic ◽  
Bire Spasojevic-De ◽  
Eddine Ghermanic ◽  
Ubavka Mioc

The X-ray structure of ammonium decavanadate hexahydrate was redetermined at a low temperature (100 K) in order to locate the hydrogen sites and to study the hydrogen bonds. The hydrogen atoms were assigned to the appropriate atomic group, NH4 + cations, and water molecules, missing to the best of our knowledge in the literature. A kappa refinement was performed to estimate the experimental atomic charges. These charges were used to generale the electrostatic potential on the molecular surfaces of decavanadate polyanions isolated from the influence of the crystal lattice. Comparisons with previous theoretical (ab initio) calculations were made and are also discussed. .


2007 ◽  
Vol 62 (2) ◽  
pp. 215-219 ◽  
Author(s):  
Hans Reuter ◽  
Shouassi Kamaha ◽  
Otmane Zerzouf

Strontium hydroxide octahydrate Sr(OH)2 · 8 H2O crystallizes in the tetragonal space group P4/ncc with cell constants a = 9.017(1) and c = 11.603(1) Å . The crystal structure has been refined from 2656 diffractometer data up to 2ϑ = 60° to an R value of 0.0303. With the new diffraction data it was possible to localize the positions of all hydrogen atoms for the first time and to describe the hydrogen bonding scheme in detail. The Sr2+ ions are square antiprismatically coordinated by eight water molecules. These {Sr(H2O)8}2+ coordination polyhedra are linked with each other via hydrogen bonds in a way that linear columns parallel to the c axis result. The two hydroxyl anions of the asymmetric unit are linked by weak hydrogen bonds and are not coordinated to strontium atoms. Like the strontium atoms, they form linear chains parallel to the c axis. Both, {Sr(H2O)8}2+ columns and OH- chains, are interconnected through two types of additional hydrogen bonds.


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