scholarly journals Synthesis, photophysical and electrochemical characterization of terpyridine-functionalized dendritic oligothiophenes and their Ru(II) complexes

2013 ◽  
Vol 9 ◽  
pp. 866-876 ◽  
Author(s):  
Amaresh Mishra ◽  
Elena Mena-Osteritz ◽  
Peter Bäuerle
Keyword(s):  
Density Functional ◽  
Dendritic Structure ◽  
Spectroscopic Properties ◽  
Coupling Reactions ◽  
Structure Property ◽  
Cross Coupling Reactions ◽  
Structure Property Relationships ◽  
Maldi Tof Mass Spectra ◽  
New Compounds

Pd-catalyzed Sonogashira cross-coupling reactions were used to synthesize novel π-conjugated oligothienylene-ethynylene dendrons and their corresponding terpyridine-based ligands. Their complexation with Ru(II) led to interesting novel metallodendrimers with rich spectroscopic properties. All new compounds were fully characterized by 1H and 13C NMR, as well as MALDI–TOF mass spectra. Density functional theory (DFT) calculations performed on these complexes gave more insight into the molecular orbital distributions. Photophysical and electrochemical studies were carried out in order to elucidate structure–property relationships and the effect of the dendritic structure on the metal complexes. Photophysical studies of the complexes revealed broad absorption spectra covering from 250 to 600 nm and high molar extinction coefficients. The MLCT emission of these complexes were significantly red-shifted (up to 115 nm) compared to the parent [Ru(tpy)2]2+ complex.

Chemical Design and Structural Chemistry of Lwir Optical Materials

1990 ◽  
Vol 216 ◽  
Author(s):  
C.K. Lowe-Ma ◽  
D.O. Kipp ◽  
T.A. Vanderah
Keyword(s):  
Crystal Structure ◽  
Electronic Configuration ◽  
Structure Type ◽  
Optical Transparency ◽  
Structure Property ◽  
Long Wavelength ◽  
Structure Property Relationships ◽  
New Compounds ◽  
Long Wavelength Infrared

ABSTRACTSome applications for long-wavelength infrared (LWIR) windows require environmental durability and mechanical strength in addition to infrared optical transparency; i.e., the windows must simultaneously serve as optical and as structural ceramics. The requirement of optical transparency at long IR wavelengths eliminates from consideration all ceramics based on oxides and other light-anion compounds, making this a particularly difficult materials problem. The structure-property relationships and chemical rationale used to guide both the screening of known compounds and the synthesis of new compounds likely to possess the desired properties rely on factors such as atomic mass, electronic configuration, coordination number, and crystal structure type.Our research has included the directed synthesis and characterization of a number of ternary indium sulfides as well as ternary calcium yttrium sulfides. Ternary indium sulfides feature both tetrahedral and octahedral coordination of indium. The crystal structure of KInS2 and its relationship to structures observed in other systems such as AIn2S4, A = Ca,Sr,Ba, is described. The crystal structure of CaY2S4 along with studies of yttrium-doped CaS are also described. The AIn2S4 compounds are more fully described in references [1] and [2].

Crystal Chemistry, Synthesis, and Characterization of Infrared Optical Materials

1989 ◽  
Vol 152 ◽  
Author(s):  
D. O. Kipp ◽  
C. K. Lowe-Ma ◽  
T. A. Vanderah
Keyword(s):  
Inorganic Compounds ◽  
Solid State Chemistry ◽  
Structure Property ◽  
X Ray Diffraction ◽  
Structure Property Relationships ◽  
Ternary Sulfide ◽  
Directed Synthesis ◽  
New Compounds ◽  
Polycrystalline Form

ABSTRACTNon-oxide inorganic compounds such as sulfides, phosphides, and mixed-anion sulfidephosphides are of interest as possible infrared window materials. Our research on the solid state chemistry and structure-property relationships of these materials includes the directed synthesis of new compounds as well as the study of compounds that have been reported in the literature but which have been incompletely characterized for this application. The present work includes investigations of three ternary sulfide systems: ZnGa2S4, AIn2S4, (A = Ca,Sr,Ba), and CaY2S4. Samples were prepared in polycrystalline form and/or as crystals. New compounds were obtained in our studies of the CaIn2S4, SrIn2S4, and CaY2S4 systems. Compounds were characterized by X-ray diffraction, elemental analysis, FMR, and thermogravimetric analysis.

scholarly journals Structure–property relationships and third-order nonlinearities in diketopyrrolopyrrole based D–π–A–π–D molecules

2017 ◽  
Vol 13 ◽  
pp. 2374-2384 ◽  
Author(s):  
Jan Podlesný ◽  
Lenka Dokládalová ◽  
Oldřich Pytela ◽  
Adam Urbanec ◽  
Milan Klikar ◽  
...  
Keyword(s):  
Emission Spectra ◽  
Coupling Reactions ◽  
Structure Property ◽  
Scanning Calorimetry ◽  
Third Order ◽  
Third Harmonic ◽  
Fundamental Properties ◽  
Cross Coupling Reactions ◽  
Structure Property Relationships ◽  
Target Molecules

Nine new quadrupolar chromophores based on diketopyrrolopyrrole were designed and prepared by cross-coupling reactions. The property tuning has been achieved by structural variation of the peripheral substituents (donor) and enlargement of the π-system. Fundamental properties of target molecules were studied by differential scanning calorimetry, electrochemistry, and absorption and emission spectra. Nonlinear optical properties were studied by measuring the third harmonic generation. The experimental data were completed by quantum-chemical calculations and structure–property relationships were elucidated.

meso-Expanded Co(III)corroles through Suzuki-Miyaura couplings: Synthesis and tunable electrocatalytic hydrogen evolutions and oxygen reductions

2021 ◽  
pp. A-I
Author(s):  
Xifeng Zhang ◽  
Wenwu Guo ◽  
Weihua Zhu ◽  
Xu Liang
Keyword(s):  
Electronic Structure ◽  
Hydrogen Evolution ◽  
Structural Characterization ◽  
Coupling Reactions ◽  
Structure Property ◽  
Electrochemical Catalysis ◽  
Oxygen Reduction Reactions ◽  
Structure Property Relationships ◽  
Hydrogen Evolution Reactions ◽  
Positional Isomerism

In this study, four meso-expanded Co(III)corroles at meta-positions through Suzuki–Miyaura coupling reactions and their structural characterization are successfully accomplished and reported. An analysis of the structure–property relationships by spectroscopy, electrochemistry and electrochemical catalysis demonstrate how the positional isomerism influence the electronic structure and their catalytic behaviors of hydrogen evolution reactions (HERs) and oxygen reduction reactions (ORRs).

scholarly journals Correction: Synthesis and characterization of novel Li-stuffed garnet-like Li5+2xLa3Ta2−xGdxO12 (0 ≤ x ≤ 0.55): structure–property relationships

2017 ◽  
Vol 46 (25) ◽  
pp. 8304-8305
Author(s):  
Dalia M. Abdel Basset ◽  
Suresh Mulmi ◽  
Mohammed S. El-Bana ◽  
Suzan S. Fouad ◽  
Venkataraman Thangadurai
Keyword(s):  
Synthesis And Characterization ◽  
Structure Property ◽  
Dalton Trans ◽  
Structure Property Relationships

Correction for ‘Synthesis and characterization of novel Li-stuffed garnet-like Li5+2xLa3Ta2−xGdxO12 (0 ≤ x ≤ 0.55): structure–property relationships’ by Dalia M. Abdel Basset, et al., Dalton Trans., 2017, 46, 933–946.

scholarly journals DFT Study of Unstrained Ketone C-C Bond Activation via Rhodium(I)-Catalyzed Suzuki-Miyaura Cross-Coupling Reactions

2019 ◽  
Author(s):  
Dengmengfei Xiao ◽  
Lili Zhao ◽  
Diego Andrada
Keyword(s):  
Density Functional ◽  
Bond Activation ◽  
Chemical Reactivity ◽  
Cross Coupling ◽  
Underlying Mechanism ◽  
Reductive Elimination ◽  
Coupling Reactions ◽  
Co Catalysts ◽  
Cross Coupling Reactions ◽  
Strain Model

Unstrained cyclic ketones can participate in cooperative Suzuki-Miyaura cross-coupling type reaction using rhodium(I)-based catalyst via C-C bond activation. The regioselectivity indicates a trend where the most substituted side is activated and it is controlled by the beta-substituents. In this work, Density Functional Theory (DFT) calculations have been carried out to disclose the underlying mechanism in the reaction of a ketone series and arylboronate using ylidene as ancillary ligand and pyridine as co-catalysts. The computed energies suggest the reductive elimination step with the highest energy while the reductive elimination has the highest energy barrier. By the means of the Activation Strain Model (ASM) of chemical reactivity, it is found that the ketone strain energy released on the oxidative addition does not control the relativity of the OA reactivity, but indeed is the interaction energy between Rh(I) and C-C bond the ruling effect. The effect of the beta-substituents on regioselectivity has been additionally studied.

scholarly journals Structure–Property Relationships in Transition Metal Dichalcogenide Bilayers under Biaxial Strains

Nanomaterials ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2639
Author(s):  
Pingping Jiang ◽  
Pascal Boulet ◽  
Marie-Christine Record
Keyword(s):  
Density Functional ◽  
Compressive Strain ◽  
Bond Critical Point ◽  
Transition Metal Dichalcogenide ◽  
Structure Property ◽  
Photovoltaic Properties ◽  
Functional Theory ◽  
Leading Role ◽  
Structure Property Relationships

This paper reports a Density Functional Theory (DFT) investigation of the electron density and optoelectronic properties of two-dimensional (2D) MX2 (M = Mo, W and X = S, Se, Te) subjected to biaxial strains. Upon strains ranging from −4% (compressive strain) to +4% (tensile strain), MX2 bilayers keep the same bandgap type but undergo a non-symmetrical evolution of bandgap energies and corresponding effective masses of charge carriers (m*). Despite a consistency regarding the electronic properties of Mo- and WX2 for a given X, the strain-induced bandgap shrinkage and m* lowering are strong enough to alter the strain-free sequence MTe2, MSe2, MS2, thus tailoring the photovoltaic properties, which are found to be direction dependent. Based on the quantum theory of atoms in molecules, the bond degree (BD) at the bond critical points was determined. Under strain, the X-X BD decreases linearly as X atomic number increases. However, the kinetic energy per electron G/ρ at the bond critical point is independent of strains with the lowest values for X = Te, which can be related to the highest polarizability evidenced from the dielectric properties. A cubic relationship between the absolute BD summation of M-X and X-X bonds and the static relative permittivity was observed. The dominant position of X-X bond participating in this cubic relationship in the absence of strain was substantially reinforced in the presence of strain, yielding the leading role of the X-X bond instead of the M-X one in the photovoltaic response of 2D MX2 material.

scholarly journals Structure-Property Relationships of 2D Ga/In Chalcogenides

Nanomaterials ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2188
Author(s):  
Pingping Jiang ◽  
Pascal Boulet ◽  
Marie-Christine Record
Keyword(s):  
Density Functional ◽  
Lattice Mismatch ◽  
Decisive Role ◽  
Interatomic Interaction ◽  
Structure Property ◽  
Functional Theory ◽  
Structure Property Relationships ◽  
Structure Property Relationship ◽  
Maximum Conversion Efficiency

Two-dimensional MX (M = Ga, In; X = S, Se, Te) homo- and heterostructures are of interest in electronics and optoelectronics. Structural, electronic and optical properties of bulk and layered MX and GaX/InX heterostructures have been investigated comprehensively using density functional theory (DFT) calculations. Based on the quantum theory of atoms in molecules, topological analyses of bond degree (BD), bond length (BL) and bond angle (BA) have been detailed for interpreting interatomic interactions, hence the structure–property relationship. The X–X BD correlates linearly with the ratio of local potential and kinetic energy, and decreases as X goes from S to Te. For van der Waals (vdW) homo- and heterostructures of GaX and InX, a cubic relationship between microscopic interatomic interaction and macroscopic electromagnetic behavior has been established firstly relating to weighted absolute BD summation and static dielectric constant. A decisive role of vdW interaction in layer-dependent properties has been identified. The GaX/InX heterostructures have bandgaps in the range 0.23–1.49 eV, absorption coefficients over 10−5 cm−1 and maximum conversion efficiency over 27%. Under strain, discordant BD evolutions are responsible for the exclusively distributed electrons and holes in sublayers of GaX/InX. Meanwhile, the interlayer BA adjustment with lattice mismatch explains the constraint-free lattice of the vdW heterostructure.

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