logo
    Two 5-tetrazolylazo-8-hydroxyquinoline-based Zn(II) and Mn(II) complexes: syntheses, structures and optical properties
    3
    Citation
    29
    Reference
    10
    Related Paper
    Citation Trend
    Abstract:
    AbstractTwo 5-tetrazolylazo-8-hydroxyquinoline (TTHQ) Zn2+ and Mn2+ complexes, [Zn(TTHQ)(en)]·2H2O (en = ethylenediamine) (1) and [Mn2(TTHQ)2(H2O)6]·2H2O (2), were synthesized and characterized by single-crystal X-ray diffraction analysis. Stacking (π–π) and hydrogen-bonding interactions are responsible for the stabilization of the supramolecular structures. UV–vis spectral changes and photoluminescent properties of TTHQ, 1 and 2 were investigated and a red emission was found. The hydrogen-bonding interaction energies in 1 and 2 were calculated using density functional theory at the WB97XD/6-31++G level.Keywords: 8-Hydroxyquinoline derivativesCrystal structureRed photoluminescenceDFT Disclosure statementNo potential conflict of interest was reported by the authors.Additional informationFundingThis work was supported by the National Natural Science Foundation of China [grant number 21271052]; Science and Technology Program Foundation of Guangzhou [grant number 2013J4100016]; Program Foundation of the Second Batch of Innovation Teams of Guangzhou Bureau of Education [grant number 13C04].
    Keywords:
    8-Hydroxyquinoline
    Ethylene diamine
    Abstract Five new mixed ligand cobalt(III) complexes containing ethylenediamine(or R-propylenediamine)tetra(or tri)acetate and ethylenediamine have been obtained by the reactions of [Co(edta)]− and [Co(R-pdta)]− with ethylenediamine in water. The reactivity of these mixed complexes with ethylenediamine contradicts the mechanism of the reactions of [Co(edta)]− and [Co(pdta)]− with ethylenediamine proposed by Busch et.al.
    Ethylene diamine
    Isolation
    Characterization
    Citations (7)
    The stacking of layers forming three-dimensional periodic structures is explored in the general case, where neither the layers nor the stacking need to be close-packed, and the connectivity number for the system may be either two or four. Procedures are described whereby all possible stacking variants can be systematically derived for a given number of layers, and for a given number of possible stacking positions. The latter depends on the structure of the layer and on the stacking vector.
    In this work, we present a detailed investigation of the low temperature emission properties of ZnSeO alloys by means of photoluminescence, micro-photoluminescence, and time-resolved photoluminescence. We show that the low temperature broad photoluminescence spectrum of ZnSeO attributed to the recombination of localized excitons is composed of sharp lines related to individual trapping states. Based on studies of photoluminescence thermal quenching from individual trapping states and photoluminescence dynamics, the mechanism of nonradiative recombination in ZnSeO alloys is discussed. Moreover, an unexpected decrease of the low temperature Stokes shift with increasing oxygen content is observed in contrast to what has been reported for GaAs based highly mismatched alloys. The possible origin of this effect is proposed.
    Photoluminescence excitation
    Citations (5)
    Parallel stacking interactions between pyridines in crystal structures and the influence of hydrogen bonding and supramolecular structures in crystals on the geometries of interactions were studied by analyzing data from the Cambridge Structural Database (CSD). In the CSD 66 contacts of pyridines have a parallel orientation of molecules and most of these pyridines simultaneously form hydrogen bonds (44 contacts). The geometries of stacked pyridines observed in crystal structures were compared with the geometries obtained by calculations and explained by supramolecular structures in crystals. The results show that the mean perpendicular distance (R) between pyridine rings with (3.48 Å) and without hydrogen bonds (3.62 Å) is larger than that calculated, because of the influence of supramolecular structures in crystals. The pyridines with hydrogen bonds show a pronounced preference for offsets of 1.25–1.75 Å, close to the position of the calculated minimum (1.80 Å). However, stacking interactions of pyridines without hydrogen bonds do not adopt values at or close to that of the calculated offset. This is because stacking interactions of pyridines without hydrogen bonds are less strong, and they are more susceptible to the influence of supramolecular structures in crystals. These results show that hydrogen bonding and supramolecular structures have an important influence on the geometries of stacked pyridines in crystals.
    Crystal Engineering
    Crystal (programming language)
    Supramolecular assembly
    Citations (12)
    We examined the change in photoluminescence spectra of porous Si when it is oxidized then deoxidized chemically. After both steps, photoluminescence shifted to higher frequencies and increased in intensity. These shifts to higher frequencies indicate the photoluminescence is a result of the quantum size effect. Moreover, the increase in photoluminescence intensity after oxidation suggests that termination by hydrogen on the porous Si surface does not always play a key role in the photoluminescence mechanism.
    Photoluminescence excitation
    Citations (109)
    Abstract [60,70]-Fullerene–ethylenediamine microparticles with sub-μm size were obtained by simply mixing fullerene and ethylenediamine in organic solvents under ambient condition. Amazingly, well-defined rhombic dodecahedral particles were obtained for C70–ethylenediamine adducts only in the mixing ratio of C70:ethylenediamine = 1:1000.
    Ethylene diamine
    Citations (20)
    Abstract The physical characteristics of supramolecular assemblies composed of small building blocks are dictated by molecular packing patterns in the solid‐state. Yet, the structure–property correlation is still not fully understood. Herein, we report the unexpected cofacial to herringbone stacking transformation of a small aromatic bipyridine through co‐assembly with acetylated glutamic acid. The unique solid‐state structural transformation results in enhanced physical properties of the supramolecular organizations. The co‐assembly methodology was further expanded to obtain diverse molecular packings by different bipyridine and acetylated amino acid derivatives. This study presents a feasible co‐assembly approach to achieve the solid‐state stacking transformation of supramolecular organization and opens up new opportunities to further explore the relationship between molecular arrangement and properties of supramolecular assemblies by crystal engineering.
    Crystal Engineering
    Supramolecular assembly
    Citations (37)
    Abstract The physical characteristics of supramolecular assemblies composed of small building blocks are dictated by molecular packing patterns in the solid‐state. Yet, the structure–property correlation is still not fully understood. Herein, we report the unexpected cofacial to herringbone stacking transformation of a small aromatic bipyridine through co‐assembly with acetylated glutamic acid. The unique solid‐state structural transformation results in enhanced physical properties of the supramolecular organizations. The co‐assembly methodology was further expanded to obtain diverse molecular packings by different bipyridine and acetylated amino acid derivatives. This study presents a feasible co‐assembly approach to achieve the solid‐state stacking transformation of supramolecular organization and opens up new opportunities to further explore the relationship between molecular arrangement and properties of supramolecular assemblies by crystal engineering.
    Crystal Engineering
    Supramolecular assembly
    Physical property
    Citations (6)