scholarly journals Die kristallinen Hydrate von Tetramethylammoniumfluorid. Bildung, Struktur, Wasserstoffbrückenbindung [1] / The Crystalline Hydrates of Tetramethylammonium Fluoride. Formation, Structure, Hydrogen Bonding

1993 ◽  
Vol 48 (8) ◽  
pp. 1057-1064 ◽  
Author(s):  
Dieter Stäben ◽  
Dietrich Mootz
Keyword(s):  
Crystal Structure ◽  
Three Dimensional ◽  
Membered Ring ◽  
Dense Layer ◽  
Melting Diagram ◽  
Temperature Dependent ◽  
X Ray ◽  
Dimensional Network ◽  
First Time ◽  
Crystalline Hydrates

The melting diagram of the system Me4NF-H2O in the region 50-100 mol% H2O has been investigated for the first time, using DTA, DSC and temperature-dependent X-ray powder diffraction. Four crystalline hydrates Me4NF·xH2O were found, with x = 1,2.33,4 and 5, which decompose irreversibly above ca. 160°C and melt incongruently at 36°C, congruently at 46°C and again incongruently at 10°C, respectively. The crystal structure of each hydrate, except the already known one of the tetrahydrate, has been determined with MoKa diffractometer data. The monohydrate is rhombohedral with space group R3̄̄m and Z = 6 formula units per unit cell (hexagonal axes), the 2.33-hydrate monoclinic with P21/n and Z = 12, and the pentahydrate tetragonal with I4̄2 m and Z = 2. The hydrogen-bonded H2O/F- structure is an isolated centrosymmetric [F2(H2O)2]2- four-membered ring in the monohydrate, a rather open three-dimensional network in the 2.33-hydrate and a corrugated dense layer of fused fivemembered rings in the pentahydrate.

Crystal and Molecular Structure of 3-Iodo-2-propynyl-N-butylcarbamate

1997 ◽  
Vol 52 (2) ◽  
pp. 256-258 ◽  
Author(s):  
Evgeni V. Avtomonov ◽  
Rainer Grüning ◽  
Jörg Lorberth
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Title Compound ◽  
Crystal And Molecular Structure ◽  
Three Dimensional ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dimensional Network ◽  
Carbamate Group ◽  
Oxygen Atoms

Abstract The crystal structure of the title compound has been determined by X-ray diffraction methods. Due to the Lewis acidic character of the iodine substituent a “zig-zag” chain is formed via intermolecular interactions (2.933(4) A) between iodine and oxygen atoms of theocarbamate moiety. A three-dimensional network is formed through hydrogen-bridging (2.04 A) between NH-groups and the oxygen atoms of the neighbouring carbamate group of the next molecule.

Crystal structure of (Z)-cefprozil monohydrate, C18H19N3O5S(H2O)

2019 ◽  
Vol 34 (4) ◽  
pp. 379-388
Author(s):  
Zachary R. Butler ◽  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton
Keyword(s):  
Crystal Structure ◽  
Powder Diffraction ◽  
Density Functional ◽  
Three Dimensional ◽  
Ion Pair ◽  
Powder Diffraction Data ◽  
Powder Diffraction File ◽  
X Ray ◽  
Dimensional Network ◽  
Acid Proton

The crystal structure of cefprozil monohydrate has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Cefprozil monohydrate crystallizes in space group P21 (#4) with a = 11.26513(6), b = 11.34004(5), c = 14.72649(11) Å, β = 90.1250(4)°, V = 1881.262(15) Å3, and Z = 4. Although a reasonable fit was obtained using an orthorhombic model, closer examination showed that many peaks were split and/or had shoulders, and thus the true symmetry was monoclinic. DFT calculations revealed that one carboxylic acid proton moved to an amino group. The structure thus contains one ion pair and one pair of neutral molecules. This protonation was confirmed by infrared spectroscopy. There is an extensive array of hydrogen bonds resulting in a three-dimensional network. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™.

Structure and Properties of [(CH2OH)3CNH3]H2AsO4

2003 ◽  
Vol 58 (12) ◽  
pp. 722-726 ◽  
Author(s):  
A. Waśkowska ◽  
S. Dacko ◽  
Z. Czapla
Keyword(s):  
Phase Transition ◽  
Second Harmonic ◽  
Three Dimensional ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Dimensional Network ◽  
Network Of Hydrogen Bonds ◽  
Dependent Behaviour

Crystals of [(CH2OH)3CNH3]H2AsO4 have been grown, and X-ray diffraction analysis has shown them to be monoclinic, with space group P21. A three-dimensional network of hydrogen bonds of the type O-H. . . O and N-H. . . O forms strong cation-cation and cation-anion linkages. Stabilizing the structure, they create favourable conditions in the crystal to be polar. The temperature dependent behaviour of the dielectric permittivity, measured along three crystal axes in the range 100 - 300 K, did not show any evidence for a phase transition, while the pyroelectric properties of the crystal confirmed the lack of a centre of symmetry. These polar features locate [(CH2OH)3CNH3]H2AsO4 among the materials applicable to electrooptics and for the second harmonic generation.

New Inclusion Compounds of Selenourea with Tetraethyl- and Tetra-n-propylammonium Halides

1997 ◽  
Vol 53 (2) ◽  
pp. 262-271 ◽  
Author(s):  
Q. Li ◽  
T. C. W. Mak
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Crystal Data ◽  
Tetraethylammonium Chloride ◽  
Space Group ◽  
X Ray ◽  
X Ray Crystallography ◽  
Dimensional Network ◽  
Single Column

Air-sensitive selenourea inclusion complexes tetraethylammonium chloride–selenourea (1/2), (C2H5)4N+.C1−.2[(NH2)2CSe] (1), tetra-n-propyl-ammonium chloride–selenourea (1/3), (n-C3H7)4N+.C1−.3[(NH2)2CSe] (2), tetra-n-propylammonium bromide–selenourea (1/3), (n-C3H7)4N+.Br−.3[(NH2)2CSe] (3), and tetra-n-propylammonium iodide–selenourea (1/1), (n-C3H7)4N+.I−.(NH2)2CSe (4), have been prepared and characterized by X-ray crystallography. Crystal data, Mo Kα radiation: (1), space group P21/n, Z = 4, a = 8.768 (5), b = 11.036 (6), c = 19.79 (1) Å, β = 96.92 (1)°, R F = 0.055 for 1468 observed data; (2), space group Cc, Z = 4, a = 18.091 (4), b = 13.719 (3), c = 11.539 (2) Å, β = 111.93 (3)°, R F = 0.051 for 1187 observed data; (3), space group Cc, Z = 4, a = 18.309  (4), b = 13.807 (3), c = 11.577 (2) Å, β = 112.45 (3)°, R F = 0.049 for 1592 observed data; (4), space group P21/n, Z = 4, a = 8.976 (1), b = 14.455 (2), c = 15.377 (3) Å, β = 94.16(1)°, R F = 0.062 for 1984 observed data. In the crystal structure of (1) the parallel alternate arrangement of selenourea–chloride ribbons and selenourea chains generates a puckered layer and the cations are sandwiched between them. In the isomorphous complexes (2) and (3) wide selenourea–halide double ribbons are crosslinked by bridging selenourea molecules via N—H...Se and N—H...X hydrogen bonds [average N...Se = 3.521 (8) and 3.527 (7), N...Cl = 3.354 (8) and N...Br = 3.500 (7) Å in (2) and (3), respectively] to form a channel-like three-dimensional network and the cations are accommodated in a single column within each channel. In the crystal structure of (4) the selenourea molecules are joined in the shoulder-to-shoulder fashion via N—H...Se hydrogen bonds [N...Se = 3.529 (7) and 3.534 (7) Å] to generate a ribbon and each selenourea molecule also forms a pair of chelating N—H...I hydrogen bonds [N...I = 3.567 (7) and 3.652 (7) Å] to an adjacent iodide ion.

scholarly journals Synthesis, crystal structure and charge-distribution validation of a new alluaudite-type phosphate, Na2.22Mn0.87In1.68(PO4)3

2020 ◽  
Vol 76 (8) ◽  
pp. 1369-1372
Author(s):  
Abdessalem Badri ◽  
Inmaculada Alvarez-Serrano ◽  
María Luisa López ◽  
Mongi Ben Amara
Keyword(s):  
Crystal Structure ◽  
Single Crystals ◽  
Three Dimensional ◽  
Structure Type ◽  
X Ray Diffraction ◽  
Flux Method ◽  
X Ray ◽  
Coordination Numbers ◽  
Dimensional Network ◽  
Anionic Framework

Na2.22Mn0.87In1.68(PO4)3, sodium manganese indium tris(phosphate) (2.22/0.87/1.68), was obtained in the form of single crystals by a flux method and was structurally characterized by single-crystal X-ray diffraction. The compound belongs to the alluaudite structure type (space group C2/c) with general formula X(2)X(1)M(1)M(2)2(PO4)3. The X(2) and X(1) sites are partially occupied by sodium [occupancy 0.7676 (17) and 1/2] while the M(1) and M(2) sites are fully occupied within a mixed distribution of sodium/manganese(II) and manganese(II)/indium, respectively. The three-dimensional anionic framework is built up on the basis of M(2)2O10 dimers that share opposite edges with M(1)O6 octahedra, thus forming infinite chains extending parallel to [10\overline{1}]. The linkage between these chains is ensured by PO4 tetrahedra through common vertices. The three-dimensional network thus constructed delimits two types of hexagonal channels, resulting from the catenation of M(2)2O10 dimers, M(1)O6 octahedra and PO4 tetrahedra through edge- and corner-sharing. The channels are occupied by Na+ cations with coordination numbers of seven and eight.

scholarly journals Crystal structure of melaminium cyanoacetate monohydrate

2020 ◽  
Vol 76 (10) ◽  
pp. 1645-1648
Author(s):  
Bhawani Sigdel Regmi ◽  
Allen Apblett ◽  
Douglas Powell
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Water Molecule ◽  
Title Compound ◽  
Three Dimensional ◽  
Membered Ring ◽  
Water Molecules ◽  
Asymmetric Unit ◽  
Dimensional Network

The asymmetric unit of the title compound, 2,4,6-triamino-1,3,5-triazin-1-ium cyanoacetate monohydrate, C3H7N6 +·NCCH2COO−·H2O, consists of a melaminium cation, a cyanoacetate anion and a water molecule, which are connected to each other via N—H...O and O—H...O hydrogen bonds, generating an eight-membered ring. In the crystal, the melaminium cations are connected by two pairs of N—H...N hydrogen bonds, forming tapes along [110]. These tapes develop a three-dimensional network through N—H...O, O—H...O, N—H...N and C—H...O hydrogen bonds between the cations, anions and water molecules.

scholarly journals Synthesis, crystal structure and thermal properties of poly[bis[μ2-3-(aminomethyl)pyridine]bis(thiocyanato)cobalt(II)]

2021 ◽  
Vol 77 (4) ◽  
pp. 428-432
Author(s):  
Christoph Krebs ◽  
Inke Jess ◽  
Christian Näther
Keyword(s):  
Crystal Structure ◽  
Differential Scanning Calorimetry ◽  
Hydrogen Bonding ◽  
Thermal Properties ◽  
Powder Diffraction ◽  
Title Compound ◽  
Three Dimensional ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Dimensional Network

The reaction of Co(NCS)2 with 3-(aminomethyl)pyridine as coligand leads to the formation of crystals of the title compound, [Co(NCS)2(C6H8N2)2] n , that were characterized by single-crystal X-ray analysis. In the crystal structure, the CoII cations are octahedrally coordinated by two terminal N-bonded thiocyanate anions as well as two pyridine and two amino N atoms of four symmetry-equivalent 3-(aminomethyl)pyridine coligands with all pairs of equivalent atoms in a trans position. The CoII cations are linked by the 3-(aminomethyl)pyridine coligands into layers parallel to the ac plane. These layers are further linked by intermolecular N—H...S hydrogen bonding into a three-dimensional network. The purity of the title compound was determined by X-ray powder diffraction and its thermal behavior was investigated by differential scanning calorimetry and thermogravimetry.

Synthese, Kristallstruktur und Eigenschaften von 1,1,3,3,3-Pentaamino-1-oxo- 1λ5 ,3λ5-diphosphaz-2-en, (NH2)2(O)P-N=P(NH2)3 / Synthesis, Crystal Structure, and Properties of 1,1,3,3,3-Pentaamino-1-oxo-1λ5, 3λ5-diphosphaz-2-ene, (NH2)2(O)P-N=P(NH2)3

1996 ◽  
Vol 51 (8) ◽  
pp. 1079-1083 ◽  
Author(s):  
N. Stock ◽  
W. Schnick
Keyword(s):  
Crystal Structure ◽  
Thermal Properties ◽  
Room Temperature ◽  
Three Dimensional ◽  
Intermolecular Hydrogen Bonding ◽  
Structure And Properties ◽  
X Ray ◽  
Hydrogen Bonding Interactions ◽  
Dimensional Network ◽  
Ray Methods

Coarse crystalline (NH2)2(O)P-N=P(NH2)3 is obtained from a NH3 saturated CH2Cl2 suspension of (NH2)2(O)P-N=P(NH2)3 NH4Cl at room temperature. (NH2)2(O)P-N=P(NH2)3·NH4Cl is synthesized by slow addition of Cl2(O)P-N=PCl3 to a solution of NH3 in CH2Cl2 at -78 °C. Excess NH4Cl is removed by treatment with HNEt2 followed by extraction with CH2Cl2. The crystal structure of (NH2)2(O)P-N=P(NH2)3 has been determined by single crystal X-ray methods (P21/c; a = 1462.8(3), b = 944.8(2), c = 1026.9(2) pm, β = 110.69(3)°; Z = 8). In the unit cell there are two crystallographically unique molecules. They form a three dimensional network by intermolecular hydrogen bonding interactions (N-H···N ≥ 313 pm. N-H···O ≥ 293 pm). The investigation of the thermal properties shows decomposition with evolution of NH3 above 80 °C.

Two tautomers in one crystal: 4(5)-nitro-5(4)-methoxyimidazole

2004 ◽  
Vol 60 (2) ◽  
pp. 191-196 ◽  
Author(s):  
Maciej Kubicki
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Imidazole Derivative ◽  
Hydrogen Atoms ◽  
X Ray ◽  
Dimensional Network ◽  
Hydrogen Bond Pattern ◽  
Annular Tautomerism

The case of prototropic annular tautomerism in an imidazole derivative has been found. The crystal structure contains a 50:50 mixture of two tautomers: 4-nitro-5-methoxyimidazole and 5-nitro-4-methoxyimidazole. The X-ray experiment actually shows the superposition of these compounds; it appears as if the structure is centrosymmetric and the N—H hydrogen atoms are disordered over two ring N atoms. Owing to the hydrogen-bond pattern, the values of their site occupation factors have to be exactly equal to 1/2. The molecules are connected into a three-dimensional network by means of N—H...N and C—H...O hydrogen bonds.

scholarly journals Crystal structure of 4-(prop-2-ynyloxy)-2,2,6,6-tetramethylpiperidin-1-oxyl

2014 ◽  
Vol 70 (9) ◽  
pp. 130-133 ◽  
Author(s):  
Shailesh K. Goswami ◽  
Lyall R. Hanton ◽  
C. John McAdam ◽  
Stephen C. Moratti ◽  
Jim Simpson
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Three Dimensional ◽  
Chair Conformation ◽  
Membered Ring ◽  
Equatorial Orientation ◽  
Propargyl Bromide ◽  
Compound C ◽  
Dimensional Network

The title compound, C12H20NO2, was synthesized from 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (hydroxy-TEMPO) and propargyl bromide. The six-membered ring adopts a flattened chair conformation and carries a propynyloxy substituent in an equatorial orientation at the 4-position. The N—O bond length of the piperidin-1-oxyl unit is 1.289 (3) Å. In the crystal, C—H...O hydrogen bonds combine with unusual C—H...π interactions involving the alkyne unit as acceptor to generate a three-dimensional network.

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