Crystals Of Bis Research Articles

High pressures studies on bis(L-alaninate)copper(II) by Raman spectroscopy and synchrotron X-ray diffraction

The crystal of bis(L-alaninate)copper(II) [Cu(C3H6NO2)2] was studied by Raman spectroscopy and synchrotron X-ray diffraction as a function of hydrostatic pressure, and its vibrational and structural behavior were investigated to analyze its stability at high pressures. The Raman spectra of bis(L-alaninate)copper(II) show changes in vibrational modes that are associated with deformations and stretching of units involving the copper atom. These results indicate that molecular fragments involving the copper atom undergo rotations and discontinuities in bond lengths. The lattice parameters of bis(L-alaninate)copper(II) obtained from Le Bail fits also exhibit changes in the same pressure ranges as the Raman spectra. The discontinuities in the angular parameter beta are compatible with the rotations of the molecular fragments. Bis(L-alaninate)copper(II) undergoes changes, but maintains monoclinic symmetry in the range of 0–20.1 GPa.

Crystals of Aliphatic Derivatives of [Cu(acac)2 ] have Distinct Atomic-Scale Mechanisms of Bending.

Molecular crystals displaying elastic flexibility have important applications in the fields of optoelectronics and nanophotonic technologies. Understanding the mechanisms by which these materials bend is critical to the design of future materials incorporating these properties. Based on the known elastic properties of bis(acetylacetonato)copper(II), a series of 14 aliphatic derivatives are synthesized and crystallized. All those which grew in a needle morphology display noticeable elasticity, with 1D chains of π-stacked molecules parallel to the long metric length of the crystal a consistent crystallographic feature. Crystallographic mapping is used to measure the mechanism of elasticity at an atomic-scale. Symmetric derivatives with ethyl and propyl side chains are found to have different mechanisms of elasticity, which are further distinguished from the previously reported mechanism of bis(acetylacetonato)copper(II). While crystals of bis(acetylacetonato)copper(II) are known to bend elastically via a molecular rotation mechanism, the elasticity of the compounds presented is facilitated by expansion of their π-stacking interactions.

Bifunctional bis(2-carboxyethyl)isocyanurate crystal for high-performance photocatalytic degradation of rose bengal dye and luminescence sensing of PO43−, NO3−, Cl−, Cr2O72− and F− ions

A new crystal of bis(2-carboxyethyl)isocyanurate (KA@PS) was crystallized and employed to study its adsorption and photocatalytic properties.

A new twist on an old molecule: a rotameric isomer of bis(pentafluorophenyl)mercury

Suspending crystals of bis(pentafluorophenyl)mercury [Hg(C6F5)2] (1a) in a saturated n-hexane solution for a prolonged period results in transformation into the new polymorph [Hg(C6F5)2] (1 b) monoclinic P21/n, a = 11.7060(3) Å, b = 7.8531(2) Å, c = 13.5429(4) Å, β = 107.247(3)°, V = 1189.00(6) Å3. The C-Hg-C angle in 1 b is 177.10(11)° and the pentafluorophenyl rings are rotated 74.6(1)° to each other in comparison to 1a, the form known for 50+ years, which has a rotation angle of 58.0(2)°. Polymorph 1 b could also be obtained by crystallization from chloroform, or a CHCl3/n-hexane (1:1) mixture at −20 °C, or by seeding with a crystal of 1 b. Theoretical calculations suggest that the barrier to rotation is low.

Growth, characterization and theoretical studies of cadmium (II) thiourea complexes: a comparative study

Single crystals of bis(thiourea)cadmium(II) chloride, bis(ethylene thiourea)-cadmium(II) chloride, tris(allylthiourea)cadmium(II) chloride and tetrakis-(phenylthiourea)cadmium(II)chloride complexes were grown using conventional slow evaporation solution growth technique. The structure and crystallinity of the materials were confirmed by powder XRD analysis. The optical properties of specimens were analyzed by UV-DRS spectroscopy. FT-IR studies recognize the vibrations of functional groups present. SEM examines surface morphology. TGA and DTA expose the specimen's purity, and the decomposition was not identified until the melting point. Microhardness studies also studied the mechanical behavior of the samples. Kurtz and Perry powder technique estimates the second harmonic generation efficiency of the as-grown specimens. It is interesting to observe that the allylthiourea complex exhibits the maximum SHG efficiency. Ethylene and phenylthiourea complexes are SHG inactive since they crystallize in centrosymmetric space groups. The intermolecular interactions and crystal packing make known that close contacts are related with strong interactions.

Luminescent mesogenic dimeric borondifluoride complexes

ABSTRACT Two new families of dimeric borondifluoride complexes derived from β-enaminoketones containing terminal phenyl and naphthalenyl groups were prepared, and their mesomorphic and optical properties investigated. One single crystallographic structure of mesogenic complex 1a-BF2 (n = 12) was determined by X-ray analysis; it crystallises in a monoclinic space group P21/c and the geometry on boron atoms was all tetrahedral. The crystal was considered as linear-shaped with a length of ~51.95 Å. A relatively large dihedral angle of ~38.85° between the central phenyl spacer and tetrahedral BF2 moiety was observed. Mesomorphic properties were crucially impacted by the structure of the central spacer and terminal group; all bis(borondifluoride) complexes formed SmC or SmA phase except complexes 1b-BF2 (m = 2, 3) and 1c-BF2 . H–bond interactions supported by FT-IR spectra were attributed to the induction of SmA phase in compound 2 c-BF2 . The optical property of the boron complexes was related with their molecular structures, and they emitted blue-to-green emissions at λmax = 420–538 nm in CH2Cl2. This is the first twin liquid crystal of bis(BF2) complexes derived from Schiff baseβ-enaminoketones.

Synthesis of water-soluble zinc(ii) nitrilotris(methylenephosphonate). Molecular structure of bis(4-carboxyphenylaminium) nitrilotris(methylenephosphonate) dihydrate

Nitrilotris(methylenephosphonic)acid N[CH2P(O)(OH)2]3 (H6L) reacts with zinc oxide in an aqueous medium to give a poorly soluble polymeric crystalline salt (ZnH4L)n. The reaction proceeds through the intermediate formation of a soluble monomer complex ZnH4L. The water-soluble amorphous forms of the coordination compound used as microfertilizers were obtained by treatment of a suspension of this salt with 2-aminoethanol, 2-amino-2-(hydroxymethyl)propane-1,3-diol, 2,2′-(ethylenedioxy)bis(ethylamine). p-Aminobenzoic acid H2NC6H4COOH reacts in an aqueous solution with hexabasic nitrilotrimethylenephosphonic acid, as well as with the monomeric complex ZnH4L, giving crystals of bis(4-carboxyphenylaminium) nitrilotris(methylenephosphonate) dihydrate H4L2− · 2(H3N-C6H4-COOH)+ · 2H2O. The compounds were investigated by elemental analysis, IR and UV spectroscopy, X-ray phase analysis and X-ray diffraction analysis. Tests of the water-soluble complex with 2-aminoethanol ZnHL3− · 3(H3NCH2CH2OH)+ · 2H2O in the laboratory experiment with seeds of two agricultural crops showed a positive agronomic effect.

Photo- and Thermosensitive Molecular Crystals. Valence Tautomeric Interconversion as the Cause of the Photomechanical Effect in Crystals of Bis(dioxolene)cobalt Complex.

Especially grown crystals (elongated plates) of the complex (1,10-phen)Co(3,6-DBSQ)2 (1) reversibly elastically bend under laser excitation (532 or 808 nm) and/or heating in the temperature interval ∼242-265 K (1,10-phen = 1,10-phenanthroline, 3,6-DBSQ = anion-radical and 3,6-DBCat = dianion of 3,6-di-tert-butyl-o-benzoquinone). The abrupt interconversion of valence tautomers is observed in this temperature range: (phen)Co(3,6-DBCat)(3,6-DBSQ) ⇌ (phen)Co(3,6-DBSQ)2. Solving the problem of design of photo- (thermo-) actuators with preset parameters, the series of solid solutions of general formula (phen)x(bpy)1-xCo(3,6-DBSQ)2 was obtained and crystallized as thin elongated plates.Crystals of each solid solution demonstrate the maximal photomechanical response (bending) at a temperature close to its own valence tautomeric (VT) transition temperature. On the other hand, the VT transition temperature depends on the composition of the solid solution. So, by setting the composition of the solid solution, one can set the temperature of the photomechanical response. It is the first example of temperature-manageable photomechanical properties.

Structural diversity in the solid-state architectures of bis(4-pyridyl)acetylene and its derivatives

The crystals of bis(4-pyridyl)acetylene are orthorhombic and belong to the space group Fddd. Solid-state investigation using conventional and Hirshfeld analytical techniques revealed valuable data and structural diversities that explain the wide gap between established crystal reports of co-crystals and metal organic frameworks and the pure form of the title compound. Hirshfeld surface analysis in this wise has proved to be a useful tool in unravelling complex intermolecular interactions and simplifying them at the 2D and 3D levels using sub-tools such as fingerprint plots and electrostatic potential surfaces. Both techniques have shown that the H∙∙∙Npyr interactions in the title compound are shorter than those in its polymorphic counterpart by 0.2 Å. The more stable network provided by hetero-molecular interactions in co-crystals and metal complexes of bis(4-pyridyl)acetylene shed light on their lengthy existence compared to the less favorable homo-molecular interactions in pure molecules of bis(4-pyridyl)acetylene.

Second and third order nonlinear optical, mechanical, surface characteristics of bis(thiourea) manganese chloride (BTMC) grown by slow cooling technique used for frequency conversion applications

A semiorganic nonlinear optical (NLO) single crystal of bis(thiourea) manganese chloride (BTMC) is grown successfully by slow cooling technique using water as solvent at temperature 45 °C. The optically good quality crystal of BTMC was grown with dimension up to 8 × 8 × 2 mm3 in a period of 2–3 weeks. The grown crystal crystallizes in orthorhombic crystal system which was confirmed by single crystal X-ray diffraction analysis. The various functional groups of BTMC were identified through FT-IR spectroscopic analysis. The lower cut-off wavelength of 280 nm was revealed from optical transmittance spectrum of UV. The mechanical behavior of BTMC crystal was analyzed by Vicker’s microhardness study and also the various mechanical parameters were determined. Vickers micro hardness test revealed, the titular crystal belongs to harder material category. The SHG efficiency is estimated from Kurtz-Perry powder method and it found to be 0.33 times than the reference material. The dielectric behavior, photo conducting nature and surface properties have been analyzed for grown BTMC crystal. The presence of synthesized elements was confirmed by EDAX study. The third order nonlinear optical susceptibility chi^{left(3 right)} of the material is measured using Z-scan technique and it is found to be 5.1202 × 10−14 esu.

Molecular Organization in Crystals of Bis(diaminotriazinyl)-Substituted Derivatives of Benzene, Pyridine, and Pyrazine

The bis(diaminotriazinyl)-substituted derivatives of benzene, pyridine, and pyrazine 1–6 were made to test the ability of the 4,6-diamino-1,3,5-triazinyl group (DAT) to direct molecular organizatio...

Crystal Growth, Optical, Dielectric, Thermal, Mechanical, Laser Damage Threshold and Second Harmonic Generation Characterization of Bis 2,5-Dimethylanilinium Sulfate Single Crystal

Single crystals of bis 2,5-dimethylanilinium sulfate (bis 2,5-DAS) were grown by slow evaporation solution growth technique at room temperature. The crystalline nature of the grown crystal was confirmed by the single crystal X-ray data. Bis 2,5-DAS crystal was found to crystallize in monoclinic system with non-centrosymmetric space group Cc. The various functional groups presented in the crystal were confirmed by FT-IR spectroscopic studies. Optical transmittance of the grown crystal was studied by UV–Vis–NIR spectroscopy. The dielectric loss and dielectric constant measurement as a frequency and temperature were measured on bis 2,5-DAS single crystal. The thermal stability and decomposition stages of the grown crystal were studied by TG-DTA analysis. Microhardness measurements revealed that bis 2,5-DAS belongs to a soft material category. Laser damage threshold studies were carried out for the grown crystal. The second harmonic generation of the crystal was confirmed and the efficiency was measured using Kurtz Perry powder method.

Synthesis, structural characterization, Hirshfeld surface analysis, and theoretical investigations of bis(benzene-1,2-dicarboxylato)bis(4-methylbenzohydrazide)zinc

Single crystals of bis(benzene-1,2-dicarboxylato)bis(4-methylbenzohydrazide)zinc (ZPTH), a novel Zn(II) complex of phthalic acid and hydrazide, were grown from aqueous solution by slow evaporation solution growth technique. The compound C32H30N4O10Zn crystallizes in triclinic system with centrosymmetric space group Pī. Its structure is built up from octahedral (ZnO4N2) linked to each other through the phthalate and hydrazide groups. The good crystallinity of the as-grown specimen is confirmed by the powder X-ray diffraction pattern. The band gap energy is estimated using diffuse reflectance data by the application of Kubelka–Munk algorithm. ZPTH exhibits fluorescent emission at 401 nm in the solid state at room temperature. Theoretical calculations were performed using density functional theory (DFT) method. Experimental observations are well supported by theoretical studies.GRAPHICAL ABSTRACT

Isomorphous rare-earth bis[bis(2,6-diisopropylphenyl)phosphate] complexes and their self-assembly into two-dimensional frameworks by intramolecular hydrogen bonds.

The crystal structures of rare-earth diaryl- or dialkylphosphate derivatives are poorly explored. Crystals of bis[bis(2,6-diisopropylphenyl)phosphato-κO]chloridotetrakis(methanol-κO)neodymium methanol disolvate, [Nd(C24H34O4P)Cl(CH4O)4]·2CH3OH, (1), and of the lutetium, [Lu(C24H34O4P)Cl(CH4O)4]·2CH3OH, (2), and yttrium, [Y(C24H34O4P)Cl(CH4O)4]·2CH3OH, (3), analogues have been obtained by reactions between lithium bis(2,6-diisopropylphenyl)phosphate and LnCl3(H2O)6 (in a 2:1 ratio) in methanol. Compounds (1)-(3) crystallize in the C2/c space group. Their crystal structures are isomorphous. The molecule possesses C2 symmetry with a twofold crystallographic axis passing through the Ln and Cl atoms. The bis(2,6-diisopropylphenyl)phosphate ligands all display a κ1O-monodentate coordination mode. The coordination polyhedron for the metal atom [coordination number (CN) = 7] is a distorted pentagonal bipyramid. Each [Ln{O2P(O-2,6-iPr2C6H3)2}2Cl(CH3OH)4] molecular unit exhibits two intramolecular O-H...O hydrogen bonds, forming six-membered rings, and two intramolecular O-H...Cl interactions, forming four-membered rings. Intermolecular O-H...O hydrogen bonds connect each unit via four noncoordinating methanol molecules with four other units, forming a two-dimensional hydrogen-bond network. Crystals of bis[bis(2,6-diisopropylphenyl)phosphato-κO]tetrakis(methanol-κO)(nitrato-κ2O,O')neodymium methanol disolvate, [Nd(C24H34O4P)(NO3)(CH4O)4]·2CH3OH, (4), have been obtained in an analogous manner from NdCl3(H2O)6. Compound (4) also crystalizes in the C2/c space group. Its crystal structure is similar to those of (1)-(3). The κ2O,O'-bidentate nitrate anion is disordered over a twofold axis, being located nearly on it. Half of the molecule is crystallographically unique (CNNd = 8). Unlike (1)-(3), complex (4) exhibits disorder of all three methanol molecules, one isopropyl group of the phosphate ligand and the NO3- ligand. The structure of (4) displays intra- and intermolecular O-H...O hydrogen bonds similar to those in (1)-(3). Compounds (1)-(4) represent the first reported mononuclear bis[bis(diaryl/dialkyl)phosphate] rare-earth complexes.

Experimental and Computational Studies of Bis(thiourea) Lead Chloride: Semi-organic Material for NLO Applications

Non liner optical single crystals of bis(thiourea) lead chloride (BTLC), belonging to the semi-organic material category, have been prepared by a slow solvent evaporation process. The single crystal X-ray diffraction analysis indicated the orthorhombic crystal structure and non-centrosymmetric Pna21 space group of the BTLC crystal. The crystalline nature of BTLC has been verified by means of the high resolution XRD (HRXRD) method. With the aid of elemental analysis, the purity and the stoichiometry of the crystal have been validated. Etching studies have been performed on BTLC using water etchant. The nature of electronic transitions, significant optical constant values and single oscillator parameters have been identified through ultra violet transmittance studies. The laser damage threshold (LDT) value of BTLC has been determined from LDT analysis. Theoretical calculations have been performed using the density functional theory (DFT) and the values of polarizability, hyperpolarizability and dipole moment of BTLC have been elucidated. Natural bond analysis (NBO) has also been done in order to gain knowledge on the nature of donor-acceptor interactions and charge distributions existing in the BTLC crystal. The frontier orbital HOMO-LUMO gap analysis assisted in arriving at the values of important global chemical molecular reactivity descriptors.

Spectroscopic characterization and room-temperature structure of bis(4-aminopyridinium) dichromate

Crystals of bis(4-aminopyridinium) dichromate (C5H7N2)2[Cr2O7] (1) were isolated via slow solvent evaporation and characterized by energy dispersive spectroscopy (EDS), infrared (IR) and ultratviolet-visible (UV-Vis) spectroscopy, and single crystal X-ray diffraction. The room-temperature (RT; 298 K) phase of 1 crystallizes in the monoclinic space group P21/m. Its asymmetric unit consists of two crystallographically independent 4-aminopyridinium cations (A and B) and two halves of symmetry-independent dichromate anions (A and B). Cations and anions are linked with the aid of several moderate N–H⋯O hydrogen bonds and weak C–H⋯O interactions resulting in a three-dimensional supramolecular network. The crystal structure is further stabilized by extensive π–π stacking interactions between adjacent pyridine rings. A comparison of the structure of the RT phase of 1 and that of the low temperature (LT; 150 K) phase is described.

Halogen-bonded network of trinuclear copper(II) 4-iodo-pyrazolate complexes formed by mutual breakdown of chloro-form and nanojars.

Crystals of bis-(tetra-butyl-ammonium) di-μ3-chlorido--tris-(μ2-4-iodo-pyrazolato-κ2N:N')tris-[chlorido-cuprate(II)] 1,4-dioxane hemisolvate, (C16H36N)2[Cu3(C3H2IN2)3Cl5]·0.5C4H8O or (Bu4N)2[CuII3(μ3-Cl)2(μ-4-I-pz)3Cl3]·0.5C4H8O, were obtained by evaporating a solution of (Bu4N)2[{CuII(μ-OH)(μ-4-I-pz)} n CO3] (n = 27-31) nanojars in chloro-form/1,4-dioxane. The decomposition of chloro-form in the presence of oxygen and moisture provides HCl, which leads to the breakdown of nanojars to the title trinuclear copper(II) pyrazolate complex, and possibly CuII ions and free 4-iodo-pyrazole. CuII ions, in turn, act as catalyst for the accelerated decomposition of chloro-form, ultimately leading to the complete breakdown of nanojars. The crystal structure presented here provides the first structural description of a trinuclear copper(II) pyrazolate complex with iodine-substituted pyrazoles. In contrast to related trinuclear complexes based on differently substituted 4-R-pyrazoles (R = H, Cl, Br, Me), the [Cu3(μ-4-I-pz)3Cl3] core in the title complex is nearly planar. This difference is likely a result of the presence of the iodine substituent, which provides a unique, novel feature in copper pyrazolate chemistry. Thus, the iodine atoms form halogen bonds with the terminal chlorido ligands of the surrounding complexes [mean length of I⋯Cl contacts = 3.48 (1) Å], leading to an extended two-dimensional, halogen-bonded network along (-110). The cavities within this framework are filled by centrosymmetric 1,4-dioxane solvent mol-ecules, which create further bridges via C-H⋯Cl hydrogen bonds with terminal chlorido ligands of the trinuclear complex not involved in halogen bonding.

Photoluminescence, laser damage threshold, optical transmittance, FTIR, mechanical, dielectric, thermal and XRD studies on Bis – Glycine hydrochloride single crystal

Single crystals of Bis – glycine hydrochloride (BGHC) were grown from aqueous solution by means of slow evaporation and slow cooling techniques. Single crystal XRD study reveals that the grown BGHC crystallizes in orthorhombic system with space group P212121 and the obtained unit cell parameters are a = 5.32 Å, b = 8.10 Å and c = 18.01 Å. Powder X – ray diffraction pattern of grown BGHC has been indexed. Functional groups present in the BGHC crystals were identified by FT – IR spectral analysis. The transmission and absorption spectra for the grown BGHC crystal shows that the lower cut off wavelength lies at 235 nm. The photoluminescence spectrum of the grown crystal was recorded. Mechanical hardness of the grown BGHC was determined and Vickers microhardness hardness number was calculated. Laser damage threshold study was carried out for the grown crystal using Nd:YAG laser. The thermal stability of the grown crystal was investigated using thermogravimetric analysis and the grown crystal is thermally stable up to 198 °C. Particle size dependent second harmonic generation efficiency of the grown crystal was examined by Kurtz and Perry powder technique using 1064 nm laser.

Highly Luminous Sky-Blue Organic Light-Emitting Diodes Based on the Bis[(1,2)(5,6)]indoloanthracene Emissive Layer

An in-depth analysis of the electro-optical and light-emissive properties was carried out with a new fused heteroacene, the bis[(1,2)(5,6)]indoloanthracene. The compound was synthesized in a straightforward bidirectional manner from 1,4-dibromo-2,5-diodobenzene utilizing a reaction cascade of isomerization and cyclization sequences. Bis[(1,2)(5,6)]indoloanthracene exhibits bright luminescence with high quantum yield in solution as well as in the solid state. By using this novel semiconductor as active layer, an efficient organic light-emitting diode (OLED) has been fabricated for which its emission pattern resembles at least two emitters in a single emissive region originated from the same molecule. One has its origin from the single molecule and is similar to the luminescence spectra in solution, whereas the other functions through the formation of aggregates being similar to the emission pattern found with crystals of bis[(1,2)(5,6)]indoloanthracene. As a result, bright sky-blue OLEDs with very high lum...

Room‐Temperature Phosphorescence of Crystalline 1,4‐Bis(aroyl)‐2,5‐dibromobenzenes

AbstractThere is a growing interest in metal‐free organic luminophores that exhibit phosphorescence at room temperature. We report herein that 1,4‐bis(aroyl)‐2,5‐dibromobenzenes serve as a new class of such luminophores. The bis(aroyl)benzene derivatives were not emissive either in solution or in a doped polymer thin film. In contrast, crystals of bis(aroyl)benzenes showed photoluminescence under ambient conditions, which was subsequently confirmed as phosphorescence with a luminescence lifetime measurement. The emission color ranged from blue to green, depending on the nature of the aroyl groups, and the luminescent quantum yields were 0.05–0.18 at room temperature and 0.38–0.67 at 77 K. In each crystal, several intermolecular interactions such as C=O···H, Br···Br, C=O···Br, F···F, S···H, and MeO···H were observed, which contributed to the restriction of intramolecular motions, thereby diminishing the nonradiative decay process from the triplet excited states.