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Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials

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https://www.readbyqxmd.com/read/28362296/triclinic-crystal-structure-distortion-of-multiferroic-bimn7o12
#1
Wojciech A Sławiński, Hiroshi Okamoto, Helmer Fjellvåg
The quadruple perovskite BiMn7O12 obtained via high-pressure synthesis was investigated by high-resolution synchrotron X-ray powder diffraction over a temperature range of 10 to 295 K. Careful Rietveld analysis reveals triclinic lattice distortion of BiMn7O12 at 295 K, which increases upon cooling to 10 K. Also hkl-dependent anisotropic Bragg reflection shape was introduced to give a precise description of the diffracted intensities. Importantly BiMn7O12 crystal structure was described in the non-centrosymmetric I1 triclinic space group...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362295/variable-temperature-structural-studies-on-valence-tautomerism-in-cobalt-bis-dioxolene-molecular-complexes
#2
Venkatesha R Hathwar, Marian Stingaciu, Bo Richter, Jacob Overgaard, Bo B Iversen
A variable-temperature single-crystal structural study of five valence tautomeric cobalt molecular complexes, Co(II)(3,5-DBSQ)2(DBPy)2 (1), Co(II)(3,5-DBSQ)2(DBPy)2·1.33C7H8 (1S), Co(II)(3,5-DBSQ)2(DCPy)2·C7H8 (2S), Co(II)(3,5-DBSQ)2(TBPy)2 (3) and Co(II)(3,5-DBSQ)2(TCPy)2 (4) (S = toluene, 3,5-DBSQ = 3,5-di-tert-butylsemiquinonate, DBPy = 3,5-dibromopyridine, DCPy = 3,5-dichloropyridine, TBPy = 3,4,5-tribromopyridine and TCPy = 3,4,5-trichloropyridine) is reported. The re-crystallization of (1S) in toluene at 277 K resulted in a concomitant formation of a solvent-free polymorph, Co(II)(3,5-DBSQ)2(DBPy)2 (1)...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362294/a-potential-cu-v-organophosphonate-platform-for-tailored-void-spaces-via-terpyridine-mold-casting
#3
Aysun Bulut, Michael Wörle, Yunus Zorlu, Erdogan Kirpi, Huseyin Kurt, Jon Zubieta, Simon Grabowsky, Jens Beckmann, Gündoğ Yücesan
The reaction of appropriate copper and vanadium salts with tetratopic methane tetra-p-phenylphosphonic acid (MTPPA) in the presence of 2,2':6':2''-terpyridine (terpy) yielded the three-dimensional bimetallic copper vanadium phosphonate framework [{Cu(terpy)}4Cu(VO2)4(MTPPA-H)2]·4H2O (1). Terpy has no net contribution to the three-dimensional structure providing a potential platform for void space formation via mold-casting. The structure was characterized by single-crystal X-ray diffraction and thermogravimetric analysis (TGA)...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362293/temperature-induced-first-order-displacive-phase-transition-of-isonicotinamide-4-methoxybenzoic-acid-co-crystal
#4
Tze Shyang Chia, Ching Kheng Quah
Isonicotinamide-4-methoxybenzoic acid co-crystal (1), C6H6N2O·C8H8O3, is formed through slow evaporation from methanol solution and it undergoes a first-order isosymmetry (monoclinic I2/a ↔ monoclinic I2/a) structural phase transition at Tc = 142.5 (5) K, which has been confirmed by an abrupt jump of crystallographic interaxial angle β from variable-temperature single-crystal XRD and small heat hysteresis (6.25 K) in differential scanning calorimetry measurement. The three-dimensional X-ray crystal structures of (1) at the low-temperature phase (LTP) (100, 140 and 142 K) and the high-temperature phase (HTP) (143, 150, 200, 250 and 300 K) were solved and refined as a simple non-disordered model with final R[F(2) > 2σ(F(2))] ≃ 0...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362292/incommensurately-modulated-twin-structure-of-nyerereite-na1-64k0-36ca-co3-2
#5
Nadezhda B Bolotina, Pavel N Gavryushkin, Andrey V Korsakov, Sergey V Rashchenko, Yurii V Seryotkin, Alexander V Golovin, Bertrand N Moine, Anatoly N Zaitsev, Konstantin D Litasov
The incommensurately modulated twin structure of nyerereite Na1.64K0.36Ca(CO3)2 has been first determined in the (3 + 1)-dimensional symmetry group Cmcm(α00)00s with modulation vector q = 0.383a*. Unit-cell values are a = 5.062 (1), b = 8.790 (1), c = 12.744 (1) Å. Three orthorhombic components are related by threefold rotation about [001]. Discontinuous crenel functions are used to describe the occupation modulation of Ca and some CO3 groups. The strong displacive modulation of the O atoms in vertexes of such CO3 groups is described using x-harmonics in crenel intervals...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362291/nature-of-e2x2-%C3%AF-4c-6e-of-the-x-e-e-x-type-at-naphthalene-1-8-positions-and-model-elucidated-by-x-ray-crystallographic-analysis-and-qc-calculations-with-the-qtaim-approach
#6
Yutaka Tsubomoto, Satoko Hayashi, Waro Nakanishi, Takahiro Sasamori, Norihiro Tokitoh
The nature of E2X2 σ(4c-6e) of the X-*-E-*-E-*-X type is elucidated for 1-(8-XC10H6)E-E(C10H6X-8')-1' [(1) E, X = S, Cl; (2) S, Br; (3) Se, Cl; (4) Se, Br] after structural determination of (1), (3) and (4), together with model A [MeX---E(H)-E(H)---XMe (E = S and Se; X = Cl and Br)]. The quantum theory of atoms-in-molecules dual functional analysis (QTAIM-DFA) is applied. The total electron energy densities Hb(rc) are plotted versus Hb(rc) - Vb(rc)/2 for the interactions at the bond critical points (BCPs; *), where Vb(rc) show the potential energy densities at the BCPs...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362290/relationships-between-hydrogen-bonds-and-halogen-bonds-in-biological-systems
#7
Rhianon K Rowe, P Shing Ho
The recent recognition that halogen bonding (XB) plays important roles in the recognition and assembly of biological molecules has led to new approaches in medicinal chemistry and biomolecular engineering. When designing XBs into strategies for rational drug design or into a biomolecule to affect its structure and function, we must consider the relationship between this interaction and the more ubiquitous hydrogen bond (HB). In this review, we explore these relationships by asking whether and how XBs can replace, compete against or behave independently of HBs in various biological systems...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362289/color-tunable-phosphorescence-of-1-10-phenanthrolines-by-4-7-methyl-diphenyl-dichloro-substituents-in-cocrystals-assembled-via-bifurcated-c-i-n-halogen-bonds-using-1-4-diiodotetrafluorobenzene-as-a-bonding-donor
#8
Rui Liu, Yuan Jun Gao, Wei Jun Jin
Single-crystal X-ray diffraction reveals a series of phosphorescent cocrystals which were assembled by 1,4-diiodotetrafluorobenzene (1,4-DITFB) and either 4,7-dimethyl-1,10-phenanthroline (DMPhe), 4,7-diphenyl-1,10-phenanthroline (DPPhe) or 4,7-dichloro-1,10-phenanthroline (DClPhe) via C-I...N halogen bonding. These cocrystals, labeled (1), (2) and (3), respectively, are phosphorescent and a distinct change in phosphorescent color can be observed from orange-yellow, green to yellow-green, with well defined vibrational band maxima at 587, 520 and 611 nm for (1), (2) and (3)...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362288/crystallographic-insights-into-the-structural-aspects-of-thioctic-acid-based-halogen-bond-donor-for-the-functionalization-of-gold-nanoparticles
#9
Kavitha Buntara Sanjeeva, Ilaria Tirotta, Vijith Kumar, Francesca Baldelli Bombelli, Giancarlo Terraneo, Pierangelo Metrangolo
The synthesis and self-assembly capabilities of a new halogen-bond donor ligand, 2,3,5,6-tetrafluoro-4-iodophenyl 5-(1,2-dithiolan-3-yl)pentanoate (1), are reported. The crystal structure of ligand (1) and the formation of a cocrystal with 1,2-di(4-pyridyl)ethylene, (1)·(2), both show halogen bonds involving the 4-iodotetrafluorobenzene moiety. Ligand (1), being a self-complementary unit, forms an infinite halogen-bonded chain driven by the S...I synthon, while the cocrystal (1)·(2) self-assembles into a discrete trimeric entity driven by the N...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362287/utilizing-bifurcated-halogen-bonding-interactions-with-the-uranyl-oxo-group-in-the-assembly-of-a-uo2-3-bromo-5-iodobenzoic-acid-coordination-polymer
#10
Mark Kalaj, Korey P Carter, Christopher L Cahill
The synthesis and crystal structure of a new uranyl coordination polymer featuring 3-bromo-5-iodobenzoic acid is described and the luminescent and vibrational properties of the material have been explored. Compound (1), [UO2(C7H3BrIO2)2]n, features dimeric uranyl units chelated and then linked by 3-bromo-5-iodobenzoic acid ligands to form a one-dimensional coordination polymer that is subsequently assembled via bifurcated halogen-bonding interactions with uranyl oxo atoms to form a supramolecular three-dimensional network...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362286/halogen-bonding-stabilizes-a-cis-azobenzene-derivative-in-the-solid-state-a-crystallographic-study
#11
Marco Saccone, Antti Siiskonen, Franisco Fernandez-Palacio, Arri Priimagi, Giancarlo Terraneo, Giuseppe Resnati, Pierangelo Metrangolo
Crystals of trans- and cis-isomers of a fluorinated azobenzene derivative have been prepared and characterized by single-crystal X-ray diffraction. The presence of F atoms on the aromatic core of the azobenzene increases the lifetime of the metastable cis-isomer, allowing single crystals of the cis-azobenzene to be grown. Structural analysis on the cis-azobenzene, complemented with density functional theory calculations, highlights the active role of the halogen-bond contact (N...I synthon) in promoting the stabilization of the cis-isomer...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362285/testing-the-tools-for-revealing-and-characterizing-the-iodine-iodine-halogen-bond-in-crystals
#12
Ekaterina Bartashevich, Irina Yushina, Kristina Kropotina, Svetlana Muhitdinova, Vladimir Tsirelson
To understand what tools are really suitable to identify and classify the iodine-iodine non-covalent interactions in solid organic polyiodides, we have examined the anisotropy of the electron density within the iodine atomic basin along and across the iodine-iodine halogen bond using the Laplacian of electron density, one-electron potential and electron localization function produced by Kohn-Sham calculations with periodic boundary conditions. The Laplacian of electron density exhibits the smallest anisotropy and yields a vague picture of the outermost electronic shells...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362284/cocrystal-assembled-by-1-4-diiodotetrafluorobenzene-and-phenothiazine-based-on-c-i-%C3%AF-n-s-halogen-bond-and-other-assisting-interactions
#13
Hui Wang, Wei Jun Jin
The halogen-bonded cocrystal of 1,4-diiodotetrafluorobenzene (1,4-DITFB) with the butterfly-shape non-planar heterocyclic compound phenothiazine (PHT) was successfully assembled by the conventional solution-based method. X-ray single-crystal diffraction analysis reveals a 3:2 stoichiometric ratio for the cocrystal (1,4-DITFB/PHT), and the cocrystal structure is constructed via C-I...π, C-I...N and C-I...S halogen bonds as well as other assisting interactions (e.g. C-H...F/S hydrogen bond, C-H...H-C and C-F...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362283/experimental-investigation-of-halogen-bond-hard-soft-acid-base-complementarity
#14
Asia Marie S Riel, Morly J Jessop, Daniel A Decato, Casey J Massena, Vinicius R Nascimento, Orion B Berryman
The halogen bond (XB) is a topical noncovalent interaction of rapidly increasing importance. The XB employs a `soft' donor atom in comparison to the `hard' proton of the hydrogen bond (HB). This difference has led to the hypothesis that XBs can form more favorable interactions with `soft' bases than HBs. While computational studies have supported this suggestion, solution and solid-state data are lacking. Here, XB soft-soft complementarity is investigated with a bidentate receptor that shows similar associations with neutral carbonyls and heavy chalcogen analogs...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362282/theoretical-insights-into-the-%C3%AF-hole-interactions-in-the-complexes-containing-triphosphorus-hydride-p3h3-and-its-derivatives
#15
Yuehong Wang, Xiaoyan Li, Yanli Zeng, Lingpeng Meng, Xueying Zhang
The π-hole of triphosphorus hydride (P3H3) and its derivatives Z3X3 (Z = P, As; X = H, F, Cl, Br) was discovered and analyzed. MP2/aug-cc-pVDZ calculations were performed on the π-hole interactions in the HCN...Z3X3 complexes and the mutual influence between π-hole interactions and the hydrogen bond in the HCN...HCN...Z3X3 and HCN...Z3X3...HCN complexes studied. The π-hole interaction belongs to the typical closed-shell noncovalent interaction. The linear relationship was found between the most positive electrostatic potential of the π-hole (VS,max) and the interaction energy...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362281/the-evaluation-of-qm-mm-driven-molecular-docking-combined-with-mm-gbsa-calculations-as-a-halogen-bond-scoring-strategy
#16
Rafał Kurczab
The combination of quantum mechanics/molecular mechanics-driven (QM/MM) molecular docking with binding free-energy calculations was successfully used to reproduce the X-ray geometries of protein-ligand complexes with halogen bonding. The procedure involves quantum-polarized ligand docking (QPLD) to obtain the QM-derived ligand atomic charges in the protein environment at the B3PW91/cc-pVTZ level and the MM/GBSA (generalized-Born/surface area) algorithm to calculate the binding free energies of resultant complexes...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362280/cyclic-networks-of-halogen-bonding-interactions-in-molecular-self-assemblies-a-theoretical-n-x-n-versus-c-x-n-investigation
#17
Ruben D Parra, Álvaro Castillo
The geometries and energetics of molecular self-assembly structures that contain a sequential network of cyclic halogen-bonding interactions are investigated theoretically. The strength of the halogen-bonding interactions is assessed by examining binding energies, electron charge transfer (NBO analysis) and electron density at halogen-bond critical points (AIM theory). Specifically, structural motifs having intramolecular N-X...N (X = Cl, Br, or I) interactions and the ability to drive molecular self-assembly via the same type of interactions are used to construct larger self-assemblies of up to three unit motifs...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362279/taking-the-halogen-bonding-hydrogen-bonding-competition-one-step-further-complexes-of-difluoroiodomethane-with-trimethylphosphine-dimethyl-sulfide-and-chloromethane
#18
Yannick Geboes, Frank De Proft, Wouter A Herrebout
To rationalize the driving factors in the competition of halogen bonding and hydrogen bonding, the complexes of the combined halogen-/hydrogen-bond donor difluoroiodomethane with the Lewis bases trimethylphosphine, dimethyl sulfide and chloromethane are studied. For all Lewis bases, ab initio calculations lead to halogen- and hydrogen-bonded complexes. Fourier transform-IR experiments involving solutions of mixtures of difluoroiodomethane with trimethylphosphine(-d9) or dimethyl sulfide(-d6) in liquid krypton confirm the coexistence of a halogen-bonded and hydrogen-bonded complex...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362278/a-new-tecton-with-parallel-halogen-bond-donors-a-path-to-supramolecular-rectangles
#19
Tharanga K Wijethunga, Marijana Đaković, John Desper, Christer B Aakeröy
A new tecton, 1,8-diiodoethynylanthracene, with two halogen-bond donor sites was synthesized and characterized. This tecton is capable of forming two parallel halogen bonds at once, which makes it a useful building block for the construction of a variety of supramolecular squares and rectangles.
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
https://www.readbyqxmd.com/read/28362277/1-3-5-tri-iodoethynyl-2-4-6-trifluorobenzene-halogen-bonded-frameworks-and-nmr-spectroscopic-analysis
#20
Patrick M J Szell, Bulat Gabidullin, David L Bryce
Halogen bonding is the non-covalent interaction between the region of positive electrostatic potential associated with a covalently bonded halogen atom, named the σ-hole, and a Lewis base. Single-crystal X-ray diffraction structures are reported for a series of seven halogen-bonded cocrystals featuring 1,3,5-tris(iodoethynyl)-2,4,6-trifluorobenzene (1) as the halogen-bond donor, and bromide ions (as ammonium or phosphonium salts) as the halogen-bond acceptors: (1)·MePh3PBr, (1)·EtPh3PBr, (1)·acetonyl-Ph3PBr, (1)·Ph4PBr, (1)·[bis(4-fluorophenyl)methyl]triphenylphosphonium bromide, and two new polymorphs of (1)·Et3BuNBr...
April 1, 2017: Acta Crystallographica Section B, Structural Science, Crystal Engineering and Materials
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