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Dicyclohexylammonium 2-methoxybenzoate
Nenad Juda?,Tomislav Portada
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808007587
Abstract: The asymmetric unit of the title compound, C12H24N+·C8H7O3 , contains one dicyclohexylammonium cation and one 2-methoxybenzoate anion. Two cations and two anions are linked together to form a four-ion cluster through a set of N—H...O hydrogen bonds. Weak C—H...O hydrogen bonds connect the clusters into chains that are stacked along the crystallographic c axis.
Diethyl (1-hydroxy-1-phenylethyl)phosphonate  [cached]
M. Nawaz Tahir,Nurcan Acar,Hamza Yilmaz,Muhammad Ilyas Tariq
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809011428
Abstract: The title compound, C12H19O4P, has a distorted tetrahedral geometry around the P atom. The molecules form dimers with R22(10) ring motifs due to intermolecular O—H...O hydrogen bonds. The double-bonded O atom of the phosphonate group behaves as an acceptor and the hydroxy group acts as a donor. Both of the ethyl groups are disordered with occupancies of 0.55:0.45 and 0.725:0.275.
Dicyclohexylammonium 3-[(hydroxymethyl)carbamoyl]propanoate  [cached]
Subadra Rajeswari,Ganesan Venkatesa Prabhu,Dhanapal Tamilvendan,Helen Stoeckli-Evans
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810044958
Abstract: The title compound, C12H24N+·C5H8NO4 , contains one dicyclohexylammonium cation and one 3-[(hydroxymethyl)carbamoyl]propanoate anion in the asymmetric unit. In the crystal, the ions are linked by intermolecular N—H...O and O—H...O hydrogen bonds, forming chains propagating along [100].
Zirconium phosphonate/1,4,5,8-naphthalenediimides self-assembled films
RODRIGUES, MAGALI A.;PETRI, DENISE F.S.;POLITI, MARIO J.;BROCHSZTAIN, SERGIO;
Anais da Academia Brasileira de Ciências , 2000, DOI: 10.1590/S0001-37652000000100010
Abstract: the formation and characterization of self-assembled films of zirconium phosphonate / n,n'-di(2-phosphonoethyl)-1,4,5,8-naphthalenediimide (dpn) is presented. the films were produced on glass substrates by deposition of alternating layers of zr+4 and dpn. films containing up to 16 layers on each side of the substrate were obtained and monitored by absorption spectroscopy and ellipsometry. when irradiated, the initially colorless films turned to a persistent pinky color reminiscent of that of dpn anion radical. these films are a promising material to the development of photovoltaic devices.
Zirconium phosphonate/1,4,5,8-naphthalenediimides self-assembled films  [cached]
RODRIGUES MAGALI A.,PETRI DENISE F.S.,POLITI MARIO J.,BROCHSZTAIN SERGIO
Anais da Academia Brasileira de Ciências , 2000,
Abstract: The formation and characterization of self-assembled films of zirconium phosphonate / N,N'-di(2-phosphonoethyl)-1,4,5,8-naphthalenediimide (DPN) is presented. The films were produced on glass substrates by deposition of alternating layers of Zr+4 and DPN. Films containing up to 16 layers on each side of the substrate were obtained and monitored by absorption spectroscopy and ellipsometry. When irradiated, the initially colorless films turned to a persistent pinky color reminiscent of that of DPN anion radical. These films are a promising material to the development of photovoltaic devices.
Diaquabis{[1-hydroxy-2-(1H-imidazol-3-ium-1-yl)ethane-1,1-diyl]bis(hydrogen phosphonato)}manganese(II)  [cached]
Zai-Chao Zhang,Rong-Qing Li,Yu Zhang
Acta Crystallographica Section E , 2009, DOI: 10.1107/s160053680905065x
Abstract: In the title compound, [Mn(C5H9N2O7P2)2(H2O)2], the MnII atom (site symmetry overline{1}) is coordinated by four phosphonate O atoms from a pair of partially deprotonated 1-hydroxy-2-(imidazol-3-yl)ethane-1,1-bisphophonic acid ligands (imhedpH3 ) and two water molecules, resulting in a slightly distorted trans-MnO6 octahedral geometry for the metal ion. In the ligands, the imidazole units are protonated and two of the hydroxy O atoms of the phosphonate groups are deprotonated and chelate the MnII, thus forming the neutral molecule of the title compound. The two protonated O atoms within the phosphonate groups of one imhedpH3 ligand act as hydrogen-bond acceptors for a bifurcated hydrogen bond originating from the coordinated water molecule. The phosphonate units of neigboring molecules are connected with their equivalents in neighboring molecules via two types of inversion-symmetric hydrogen-bonding arrangements with four and two strong O—H...O hydrogen bonds, respectively. The two interactions connect molecules into infinite chains along [111] and [110], in combination forming a tightly hydrogen-bonded three-dimensional supramolecular network. This network is further stabilized by additional hydrogen bonds between the protonated imidazole units and one of the coordinated P—O O atoms and by additional O—H...O hydrogen bonds between the water molecules and the P=O O atoms of neigboring molecules.
A second triclinic polymorph of (1-ammonio-1-phosphonoethyl)phosphonate
Natalia V. Tsaryk,Anatolij V. Dudko,Alexandra N. Kozachkova,Vasily I. Pekhnyo
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811022239
Abstract: The asymmetric unit of the second polymorph of the title compound, C2H9NO6P2, contains one molecule existing as a zwitterion. The N atom of the ammonio group is protonated and one of the phosphonic acid groups is deprotonated. Bond lengths and angles are similar in both polymorphs. Besides the differences in cell parameters, the most significant structural difference between this structure and that of the first polymorph [Dudko, Bon, Kozachkova, Tsarik & Pekhno (2008), Ukr. Khim. Zh. 74, 104–106] is the presence of strong symmetric hydrogen bonds between neighbouring phosphonate groups. H atoms involved in these hydrogen bonds are located at inversion centres and O...O distances are observed in the range 2.458 (5)–2.523 (5) . These bonds and additional O—H...O and N—H...O hydrogen bonds interlink the molecules, giving a three-dimensional supromolecular network.
Poly[diaquabis[μ-1-hydroxy-2-(imidazol-3-ium-1-yl)ethane-1,1-diyldiphosphonato]tricopper(II)]  [cached]
Yaping Li,Dajun Sun,Hu Zang,Liying Han
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536810046398
Abstract: In the title coordination polymer, [Cu3(C5H7N2O7P2)2(H2O)2]n, one CuII atom is five-coordinated by five O atoms from three 1-hydroxy-2-(imidazol-3-ium-1-yl)ethane-1,1-diyldiphosphonate (L) ligands in a distorted square-pyramidal geometry. The other CuII atom, lying on an inversion center, is six-coordinated in a distorted octahedral geometry by four O atoms from two L ligands and two O atoms from two water molecules. The five-coordinated CuII atoms are linked by phosphonate O atoms of the L ligands, forming a polymeric chain. These chains are further linked by the six-coordinated Cu atoms into a layer parallel to (overline{1}01). N—H...O and O—H...O hydrogen bonds connect the layers into a three-dimensional supramolecular structure.
Dicyclohexylammonium (S)-2-azido-3-phenylpropanoate  [cached]
Sebastian J. Petrik,Christopher L. Brown,Sue E. Boyd,Peter C. Healy
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812025536
Abstract: The asymmetric unit of the title compound, C12H24N+·C9H8N3O2 , consists of two dicyclohexylammonium cations linked to two (S)-2-azido-3-phenylpropanoate anions by four short N—H...O hydrogen bonds with N...O distances in the range 2.712 (3)–2.765 (3) . The dicyclohexylammonium cations and the aryl and carboxylate groups of the anion are related by a pseudo-inversion centre, with overall crystallographic inversion symmetry for the structure broken by the chirality of the α-C atoms of the anions.
Dicyclohexylammonium trimethylbis(hydrogen phenylphosphonato)stannate(IV)  [cached]
Tidiane Diop,Libasse Diop,Cheikh A. K. Diop,Kieran C. Molloy
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811049567
Abstract: In the title compound, (C12H24N)[Sn(CH3)3(C6H6O3P)2], the SnMe3 residues are axially coordinated by two monodentate [PhPO3H] anions, leading to a trigonal–bipyramidal geometry for the SnIV atom. The two [SnMe3(PhPO3H)2] anions in the unit cell are associated into infinite chains along the a axis by O—H...O hydrogen bonds involving the hydroxy group of the hydrogen phenylphosphonate ion. The chains interact with one another via O—H...O hydrogen bonds along the c axis. These networks of anions assemble with the dicyclohexylammonium ion through N—H...O hydrogen bonds, forming a three-dimensional network.
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