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William T A Harrison

Publications and source records attributed to William T A Harrison.

At least 19 recordsLinked to original sources
PubMed2006

Poly[propane-1,3-diyldiammonium tetra-mu-selenito-trizinc dihydrate].

The title compound, (C3H12N2)[Zn3(SeO3)4].2H2O, is built up from organic cations, {[Zn3(SeO3)4]2-}n macroanionic sheets and water molecules. The inorganic component of the structure is notable for incorporating both octahedrally and tetrahedrally coordinated Zn atoms. A network of N-H...O and O-H...O hydrogen bonds helps to establish the layered structure. The six-coordinate Zn atom has site symmetry 1, and one C and the two water O atoms have site symmetry m.

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PubMed2006

2-Bromo-1,3-bis(bromomethyl)benzene, with Z' = 1.5: whole-molecule disorder of one of the two independent molecules.

The title compound, C(8)H(7)Br(3), possesses normal geometrical parameters. There are two independent molecules; one shows whole-molecule disorder with respect to an inversion-symmetry-generated partner, while the other is undisordered. This results in the unusual situation of Z' = 1.5 and Z = 6 for a monoclinic crystal system. The undisordered molecule interacts with its neighbours by way of pi-pi stacking.

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PubMed2006

(Nitrato-kappa2O,O')bis(triethanolamine-kappa4N,O,O',O'')lanthanum(III) dinitrate.

The title compound, [La(NO3)(C6H15NO3)2](NO3)2, contains a network of [La(NO3)(C6H15NO3)2]2+ cations and nitrate counter-ions. The crystal packing is influenced by cation-to-anion O-H...O hydrogen bonds, resulting in a structure with one-dimensional character. The ten-coordinate La atom and a nitrate anion have site symmetry 2. The fact that triethanolamine can bind to such diverse cations as Li+ and La3+ militates against possible applications that require selective binding of ligand to metal.

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PubMed2006

An orthorhombic polymorph of 10,11-dihydrocarbamazepine.

The title compound (systematic name: 10,11-dihydro-5H-dibenz[b,f]azepine-5-carboxamide), C15H14N2O, is shown to crystallize as an orthorhombic polymorph to complement the known monoclinic form. The molecular conformations of both forms are very similar, involving a bent conformation for the seven-membered azepine ring and an overall ;butterfly' shape. The molecules assemble into chains by way of N-H...O bonds and N-H...pi interactions in both crystal modifications. The two polymorphs appear to form due to different van der Waals interactions between the layer-like sheets of molecules.

Carbamazepine↗
PubMed2005

A second polymorph of 2-aminopyridinium dihydrogenphosphate.

In the title compound, beta-C5H7N2+.H2PO4-, the tetrahedral dihydrogenphosphate moieties are linked into double chains by O-H...O hydrogen bonds, and the organic species crosslink the chains into sheets by way of N-H...O bonds. The resulting structure is quite different from that of the previously described alpha polymorph of this stoichiometry [Czapla, Dacko & Waskowska (2003). J. Phys. Condens. Matter, 15, 3793-3803].

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PubMed2005

Thallium(III) selenite, Tl2(SeO3)3.

The structure of Tl2(SeO3)3 [dithallium(III) triselenium(IV) nonaoxide] is monoclinic (P21/n symmetry), with all atoms in general positions. It is built up from TlO6 octahedra, distorted TlO7 pentagonal bipyramids and (SeO3)2- pyramids sharing vertices and edges to form corrugated (001) layers. The Se lone pairs of electrons are accommodated in the interlayer regions.

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PubMed2005

A 1:1 adduct of DL-threonine and arsenic acid.

The title compound, DL-threonine-arsenic acid (1/1), C4H9NO3.H3AsO4, is an unusual adduct containing zwitterionic threonine and neutral arsenic acid molecules. The component species interact by way of N-H...O and O-H...O hydrogen bonds, leading to parallel [001] chains of threonine and arsenic acid molecules which are crosslinked by further O-H...O and N-H...O bonds, resulting in a three-dimensional network.

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PubMed2005

Bis(tetra-n-butylammonium) and bis(tetraphenylphosphonium) salts of tris(2-oxo-1,3-dithiole-4,5-dithiolato)stannate(IV), both at 120 K.

The title compounds, (C16H36N)2[Sn(C3OS4)3], (I), and (C24H20P)2[Sn(C3OS4)3], (II), are examples of complex salts of the general form [Q]2[Sn(dmio)3], where Q is nBu4N+ or Ph4P+ and dmio is the 2-oxo-1,3-dithiole-4,5-dithiolate dianion. Features of both structures are the slightly distorted octahedral coordination of tin in the propeller-shaped dianions and the absence of any significant inter-anion contacts. The structure of (I) is particularly notable because all of the dianions in the sample crystal have the same propeller configuration, which is very unusual in this type of structure.

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PubMed2004

Butane-1,4-diamine zinc(II) hydrogen phosphite.

The title compound, poly[zinc(II)-mu-butane-1,4-diamine-mu-(hydrogen phosphito)] (C(4)H(12)N(2))(0.5)[ZnHPO(3)], is a hybrid organic-inorganic solid built up from 1,4-diaminobutane molecules, Zn(2+) cations (coordinated by three O atoms and one N atom) and HPO(3)(2-) hydrogen phosphite groups. The organic species bonds to the Zn atom as an unprotonated ligand, resulting in it acting as a bridge between infinite ZnHPO(3) layers, which propagate in (100). The complete butane-1,4-diamine species is generated from a H(2)N(CH(2))(2)- half molecule by inversion symmetry. The zincophosphite sheets contain polyhedral four- and eight-membered rings in a 4.8(2) topology.

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PubMed2004

beta-[H2N(CH2)2NH2]0.5[ZnHPO3], a second modification of ethylenediamine zinc hydrogen phosphite.

The title compound, poly[dizinc(II)-mu-ethylenediamine-di-mu-(hydrogen phosphito)], beta-[H(2)N(CH(2))(2)NH(2)](0.5)[ZnHPO(3)] or [Zn(2)(HPO(3))(2)(C(2)H(8)N(2))](n), is a hybrid organic/inorganic solid built up from ethylenediamine molecules (which lie about inversion centres), Zn(2+) cations (coordinated by three O atoms and one N atom) and HPO(3)(2-) hydrogen phosphite groups. The organic species bond to the Zn atom as unprotonated ligands, acting as bridges between infinite ZnHPO(3) layers that propagate as very buckled (001) sheets. The zincophosphite sheets contain polyhedral four- and eight-membered rings in a 4.8(2) topology. beta-[H(2)N(CH(2))(2)NH(2)](0.5).ZnHPO(3) complements the previously described alpha modification of the same stoichiometry [Rodgers & Harrison (2000). Chem. Commun. pp. 2385-2386].

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PubMed2004

Triethanolamine zinc phosphite, (C6H13NO3)Zn2(HPO3): a templated network or a network of clusters?

(C6H13NO3)Zn2(HPO3) (I) displays an extended hybrid organic/inorganic structure in which the triethanolamine organic species acts as an anionic tetradentate ligand, rather than a typical protonated cationic template. Crystal data for I: Mr = 357.89, monoclinic, P2(1)/c (no. 14), a = 8.4216(4) angstroms, b = 9.9262(5) angstroms, c = 12.8494(6) angstroms, beta = 91.824(1) degrees, V = 1073.6(1) angstroms3, Z = 4.

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PubMed2004

Diospyrin.

The structure of the title natural product, 1',5-dihydroxy-3',7-dimethyl-2,2'-binaphthalene-1,4,5',8'-tetrone, C(22)H(14)O(6), confirms the atomic connectivity postulated on the basis of spectroscopic data. The geometric parameters are normal and the angle between the planes of the two ring systems is 59.74 (2) degrees. The crystal packing is influenced by O-H.O hydrogen bonds, and possible short C-H.O and pi-pi stacking interactions.

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PubMed2004

The catena-arsenite chain anion, [AsO2](n)(n-): (H3NCH2CH2NH3)0.5[AsO2] and NaAsO2 (revisited).

The title compounds contain the catena-arsenite [AsO(2)](n)(n-) unit, in which the As(III) atom is pyramidally coordinated to one terminal and two bridging O atoms, resulting in an infinite anionic chain. Ethylenediammonium catena-arsenite, (C(2)H(10)N(2))(0.5)[AsO(2)], is the first example of this anion in the company of an organic cation. The ethylenediammonium species interact with the [AsO(2)](-) chains by way of N-H.O hydrogen bonds. The structure of sodium catena-arsenite, Na[AsO(2)] [Menary (1958). Acta Cryst. 11, 742-743], has been redetermined to yield more reliable geometrical parameters. The As-O distances are normal and the Na(+) cation is seven-coordinate [Na-O = 2.285 (4)-3.063 (4) A] in a distorted capped trigonal prismatic geometry.

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PubMed2004

1-Bromo-2,6-dihydroxybenzene containing R(4)(4)(8) rings and C(2) helices.

Molecules of the title compound (also known as 2-bromoresorcinol), C(6)H(5)BrO(2), are essentially planar and possess normal geometrical parameters. The crystal packing is influenced by O-H...O and O-H...O/Br hydrogen bonds and pi-pi stacking interactions, resulting in a distinctive high-symmetry structure containing R(4)(4)(8) rings and helical C(2) chains.

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