111 research outputs found
Krystalová struktura anorganických fosforečnanů
½ž ËÙÑÑ ÖÝ Ó ×× ÖØ Ø ÓÒ ½ž½ž Ñ Ó ×× ÖØ Ø ÓÒ The aim of this thesis was to solve and describe the crystal struc- ture of selected inorganic phosphates. Nine different compounds have been studied, including the NASICON type phosphates Co0.5Ti2(PO4)3, Mn0.5Ti2(PO4)3, Na3.215Fe2(PO4)3, the iron(II) diphosphate Fe2P2O7 and hydrates of rare-earth hydrogen diphosphates LnHP2O7·3H2O (Ln = Y, Tb, Dy, Yb) and TbHP2O7·4H2O. While NASICON type phos- phates and rare-earth hydrogen diphosphates have a conventional three- dimensional crystal structure, the structure of α-Fe2P2O7 is incommen- surately modulated and has been described in (3+1)-dimensional super- space. ½ž¾ž ÇÚ ÖÚ Û Ó Ø ÓÒØ ÒØ Ó ×× ÖØ Ø ÓÒ Dissertation is divided in six parts. Part 1 introduce the crystal struc- ture analysis, the concept of aperiodic crystals and the superspace ap- proach. Part 2 describes course of X-ray diffraction experiment and used experimental equipment. The next three parts, Part 3, Part 4 and Part 5, in which the structures of NASICON-type phospates, iron(II) diphos- phate, and rare-earth hydrogen diphosphates are discussed, are the main parts of this work. Part 1. Introduction and Initiation Chapter 2, "Basic principles of crystal structure analysis" con- cerns by fundamentals of crystal structure analysis, i.e. behaviour of X-...¾ž ÙØÓÖ Ö Ø Þ ÖØ ¾ž½ž Ð Þ ÖØ Cílem této práce bylo vyřešit a popsat krystalové struktury vybra- ných anorganických fosforečnanů. Bylo prozkoumáno devět různých lá- tek, a to: fosforečnany typu NASICON: Mn0,5Ti2(PO4)3 Co0,5Ti2(PO4)3, Na3,215Fe2(PO4)3, difosforečnan železnatý Fe2P2O7 a hydráty hydrogen- difosforečnanů prvků vzácných zemin LnHP2O7·3H2O (Ln = Y, Tb, Dy, Yb) a TbHP2O7·4H2O. Zatímco fosforečnany typu NASICON a hydráty hydrogendifosforečnanů prvků vzácných zemin mají konvenční třídimen- zionální krystalové struktury, struktura α-Fe2P2O7 je nesouměřitelně mo- dulovaná a byla popsána v (3 +1)-rozměrném superprostoru. ¾ž¾ž È Ð Ó × Ù Þ ÖØ Práce je rozdělena do šesti částí. Část 1 přibližuje základy strukturní analýzy krystalů, koncepci aperiodických krystalů a superprostorový pří- stup. Část 2 popisuje průběh rentgenového difrakčního experimentu a použité přístroje. Další tři části, část 3, část 4 a část 5, ve kterých jsou diskutovány struktury fosforečnanů typu NASICON, difosforečnanu že- leznatého a hydrátů hydrogendifosforečnanů prvků vzácných zemin, jsou hlavními částmi této práce. Část 1. Úvod a obeznámení s problematikou Kapitola 2, "Základní principy krystalové strukturní analýzy se zabývá základy strukturní analýzy krystalů, tj. chováním rentgenového záření, základní buňkou, symetrií,...Department of Inorganic ChemistryKatedra anorganické chemieFaculty of SciencePřírodovědecká fakult
(E)-4-Bromo-N-(2,3-dimethoxybenzylidene)aniline
The title Schiff base compound, C15H14BrNO2, was prepared by the condensation of 2,3-dimethoxybenzaldehyde with 4-bromoaniline. It adopts an E configuration with respect to the C=N bond. The dihedral angle between the two aromatic rings is 56.79 (8)°. Weak C—H⋯O and C—-H⋯π bonds can be found in the crystal structure
N,N′-Bis(2,3-dimethoxybenzylidene)propane-1,3-diamine
The title compound, C21H26N2O4, adopts an E configuration with respect to the azomethine C=N bonds. The dihedral angle between the two rings is 8.16 (8)°. The crystal structure is stabilized by weak intermolecular C—H⋯O interactions
(E)-N-(2,4-Dimethoxybenzylidene)-4-ethoxyaniline
In the title compound, C17H19NO3, the molecule has an E configuration with respect to the C=N bond and the dihedral angle between the aromatic rings is 56.07 (5)°. In the crystal, inversion dimers linked by pairs of C—H⋯O hydrogen bonds occur. The dimers are linked by weak C—H⋯π interactions, forming a three-dimensional network
Hydronium perchlorate–dibenzo-18-crown-6 (1/1): monoclinic polymorph
The asymmetric unit of the title compound, H3O+·ClO4
−·C20H24O6, contains two molecules/ions of each species. Both dibenzo-18-crown-6 molecules have a complexed hydronium ion inside their cavity with O—H⋯O and O—H⋯(O,O) links between the two species. The associated perchlorate anions also accept O—H⋯O hydrogen bonds from the hydronium ion. Both crown ether molecules are present in a butterfly conformation with approximate C
2v symmetry and their cavities are closed by the benzene ring of a neighbouring molecule. The packing is consolidated by C—H⋯O and C—H⋯π interactions
1,4,8,11-Tetraazoniacyclotetradecane diaquatetrachloridomanganese(II) dichloride dihydrate
The title compound, (C10H28N4)[MnCl4(H2O)2]Cl2·2H2O, consists of isolated octahedral [MnCl4(H2O)2]2− anions, tetraprotonated 1,4,8,11-tetraazoniacyclotetradecane cations, chloride anions and water molecules connected by a network of hydrogen bonds. The MnII atom is situated on an inversion centre, and the 1,4,8,11-tetraazoniacyclotetradecane cation is located on a mirror plane
Low-temperature superstructure of [(N,N-diisobutylcarbamoyl)methyl]octyl(phenyl)phosphine oxide (CMPO)
At 120 K, the title compound, C24H42NO2P, crystallizes in a unit cell with a doubled a parameter compared with the room-temperature structure. There are four molecules in the asymmetric unit, one of which shows extensive disorder in a 0.588 (3):0.412 (3) ratio. In the crystal, numerous C—H⋯O interactions link the molecules
4,4′-Dichloro-3,3′,5,5′-tetramethyl-2,2′-[(3aR,7aR/3aS,7aS)-2,3,3a,4,5,6,7,7a-octahydro-1H-1,3-benzimidazole-1,3-diyl)bis(methylene)]diphenol
In the title compound, C25H32Cl2N2O2, there are two intramolecular O—H⋯ N hydrogen-bonding interactions between the hydroxy groups on the aromatic rings and the two N atoms of the heterocyclic group. The cyclohexane ring adopts a chair conformation and the imidazolidine unit to which it is fused has a twisted envelope conformation. The asymmetric unit comprises one half-molecule which is completed by a twofold rotation axis. A C—H⋯O interaction is observed in the crystal structure
2-(2-Hydroxyethyl)-3-[(2-hydroxyethyl)imino]isoindolin-1-one
In the crystal structure of the title compound, C12H14N2O3, molecules are packed into layers parallel to (100). Each layer contains centrosymmetric dimers formed by a pair of strong O—H⋯N hydrogen bonds with an R
2
2(10) motif, while strong O—H⋯O hydrogen bonds forming C(10) chains connect molecules into a two-dimensional network. Additional stabilization is supplied by weak C—H⋯O hydrogen bonds and weak π–π stacking interactions with centroid–centroid distances in the range 3.4220 (7)–3.9616 (7) Å
4,4′-Dibromo-2,2′-{[(3aS,7aS)-2,3,3a,4,5,6,7,7a-octahydro-1H-1,3-benzimidazole-1,3-diyl]bis(methylidene)}diphenol
The cyclohexane ring in the title compound, C21H24Br2N2O2, adopts a chair conformation and the five-membered ring to which it is fused has a twisted envelope conformation. The asymmetric unit contains one half-molecule, which is related to the other half by a twofold rotation axis. The two N atoms of the five-membered ring are linked to the hydroxy groups by intramolecular O—H⋯N hydrogen bonds. In the crystal, intermolecular C—H⋯O and C—H⋯π interactions occur
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