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Showing 1 to 20 of 40 for “"crystal packing"”.
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Altering the Crystal Packing of Boronsubphthalocyanine Derivatives through Molecular Engineering
There are currently three known crystal packing motifs of boronsubphthalocyanine derivatives. Each motif is associated with a particular class of BsubPc derivatives, and none are ideal for organic electronic applications according to the criteria we defined for evaluation: having a continuous …
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Determinants of crystal packing by nucleic acid polymers : examples of Z-DNA and cytosine-tetraplex crystal structures
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1998.
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2,4,6-Tris(isopropylamino)-1,3,5-trinitrobenzene : Probing the Impact of Crystal Packing Forces in the Dimorphs and the Cocrystals–Experimental and Theoretical Study
… and theoretically) of conformational effects of crystal packing. Here we describe their investigation by X-ray diffraction, thermal analysis, and computational methods (force field and ab-initio). The crystal and molecular structures were determined by X-ray diffraction. For thermal analysis …
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Geometric techniques for molecular shape analysis
… conformational stability, molecular solubility, crystal packing, and docking. Various models based on a union of balls representation have been suggested for representing molecular shape, including the van der Waals model, the solvent accessible surface, and the molecular surface.
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Structural aspects of pressure- and temperature-induced phase transitions in low-dimensional systems
… in diamond anvil cells by means of single-crystal synchrotron X-ray diffraction and by complementary techniques including Raman and Mossbauer spectroscopies and powder X-ray diffraction. The results reveal a plethora of high-pressure phase transitions in MOCl. A structural analysis allowed …
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Alkynylated acenothiadiazoles and N-heteroacenes: synthesis, functionalization, and study of the optical properties for optoelectronic and sensory materials
… group aides in directing the packing motif as well as vastly increases the solubility over unsubstituted analogues. A requisite precursor in the synthesis of alkynylated N-heteroacenes is alkynylated acenothiadiazoles. These thiadiazoles display interesting photophysical …
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Structures and thermal decompositions of pseudopolymorphs of sulfonamide drugs
… succinylsulfathiazole, have been prepared by recrystallization of the drugs from various organic solvents and their properties have been studied by several physicochemical methods. Thermal Analysis involving Thermal Gravimetry (TG) and Differential Scanning Calorimetry (DSC) were used to …
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Structure and thermodynamics of Diol inclusion compounds
… 2,6-dimethylpyridine) have been solved by single crystal X-ray diffraction methods. The crystal packing modes and hydrogen bonding schemes have been elucidated, while the guest cavities have been investigated. The thermal stability of the complexes was analysed by thermogravimetric analyses and …
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Hydrogen Bonded Liquid Crystals from Fluorophenols and Alkoxystilbazoles
… stilbazoles and 3- and 4-nitrophenol. Nine X-ray crystallographic structures of the 4-octyoxy-4’-stilbazole complexed with fluorophenols were also obtained. Eight of the complexes crystallised in the space group, with a back-to-back dimer motif, while the complex of 4-fluorophenol crystallised in …
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Structural studies of organic crystals of pharmaceutical relevance. Correlation of crystal structure analysis with recognised non-bonded structural motifs in the organic solid state
… techniques and correlation of these results with crystal structural database to establish the presence of physical motifs in selected systems. Structural motifs were identified by the use of single crystal and crystal packing analysis on diverse range of pharma-relevant materials including …
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Sintesi e coordinazione di leganti Ciclopentadienilici O-Multifunzionalizzati
… of one couple of enantiomeric pairs in the crystal structure, whilst the crystal packing shows an interesting self-organization in chains of dimeric units of 1a, promoted by strong intermolecular hydroxyl H-bonding. This effect has been exploited by performing VT NMR experiments in different …
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Molecular mechanics calculations of tin-bis (triphenylphosphine oxide) complexes
… than the traditional harmonic approximations~ Crystal packing influences on the MOP angle were explored thr"ollgh ttle inclusion of the isolated molecule withil1 a shell cc)ntaini11g tl1e nearest neigl1'bors duri.rlg energy rninimization experiments~ This was found to further improve the fit of …
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Molecular studies of natural products and related compounds.
… structures, and where appropriate the effect of crystal packing forces noted. In some instances the biosynthetic pathways of the compounds are studied in more detail. The work involves the use of several complex computer programme packages, and the manipulation of these is described when …
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1. X-ray crystallographic analyses of the gene V protein from Ff bacteriophage, a single-stranded DNA-binding protein, and its Y41 mutants 2. X-ray crystallographic analyses of several anticancer drugs and their interactions with DNA
… namely Y41F and Y41H, have been studied by X-ray crystallography to high resolution. Y41F GVP crystallized isomorphously to the wild-type, while Y41H GVP crystallized in a different space group (P2$\sb12\sb12\sb1).$ Y41H GVP structure has been solved by the molecular replacement method. In both …
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Near-Infrared Luminescent Lanthanide Complexes of Quinolinol Ligands: Structure/Properties Relationship
… by the supramolecular interactions in the crystal packing. The study of the magnetic properties of erbium quinolinolates evidences small magnetic interactions, due to the supramolecular arrangement, relevant in the optical behaviour of optically active ErIII derivatives. The lanthanide …
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The design and synthesis of polycyclic conjugated hydrocarbons via the incorporation of bifunctional Diels-Alder building blocks
… linkage in the acene-like backbone. Crystal packing, spectroscopic and electrochemical properties of the molecules are described. In Chapter 3, we describe the synthesis of a set of naphthazarin-containing polycyclic conjugated hydrocarbons, which were accessed through sequential …
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Crystal structure prediction. A molecular modellling study of the solid state behaviour of small organic compounds.
The knowledge of the packing behaviour of small organic compounds in crystal lattices is of great importance for industries dealing with solid state materials. The properties of materials depend on how the molecules arrange themselves in a crystalline environment. Crystal structure prediction …
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The preparation of organosulfur derived electron transfer salts
… thesis is to effect greater control over the crystalline state of radical cation salts in order to enhance electron transport, and to allow for the incorporation of additional functionality such as optical activity or magnetism. The salts formed are based on the …
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Crystal structure prediction. A molecular modellling study of the solid state behaviour of small organic compounds.
The knowledge of the packing behaviour of small organic compounds in crystal lattices is of great importance for industries dealing with solid state materials. The properties of materials depend on how the molecules arrange themselves in a crystalline environment. Crystal structure prediction …
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The effects of strain on the electronic and optical properties of rubrene single crystals
… localised by dynamic disorder present in the crystal due to molecular vibrations. This theory has succeeded in explaining many phenomena seen in organic crystals but there are still uncertainties about how best to optimise materials for specific properties based on transient localisation …
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