Engineering Commons^™

Dft Study Of Quantum Chemical Parameters Of 4-Amino-2-Mercaptobenzimidazole And Their Tautomeric Forms, Dilnoza Rahmonova, Alisher Eshimbetov, Lobar Gapurova, Zuhra Ch. Kadirova, Shakhnoza Kadirova

CHEMISTRY AND CHEMICAL ENGINEERING

Coordination competing donor centers, electronic and geometric structures of the 4-amino-2-mercaptobenzimidazole ligand molecule were studied using quantum chemical calculation by the DFT / 6-31G method (d, p). It was shown that during the formation of the metal complex, the ligand is coordinated through the localized nitrogen atom of the imidazole ring. In this study, the total energies (Etot) of 4-amino-2-mercaptobenzimidazole (1) and its tautomeric forms (2 and 3) were calculated. And also, the energies of boundary molecular orbitals, the energy gap between boundary MOs (ΔE) and the distribution of the total charge on atoms and boundary orbitals were determined. In …

Influence Of Surfactants On The Formation And Growth Of Cadmium Telluride Nanoplatelets, A.S. Akhmetova, A.K. Ospanova, B.N. Yussupbekova, T.T. Alibay

Eurasian Journal of Physics and Functional Materials

The article presents a comprehensive review of the current research on the use of surfactants in CdTe nanoplatelet synthesis, including a discussion of the various types of surfactants that have been used and their effects on nanoplatelet size, shape, and optical properties. Additionally, the article examines the mechanisms by which surfactants influence the growth and morphology of CdTe nanoplatelets, with a focus on the role of surfactant, size, and structure. Overall, this article provides a detailed analysis of the use of surfactants in the synthesis of CdTe nanoplatelets and highlights the potential for this approach to improve the performance of …

Synthesis And Spectroscopic Study Of Complex Compounds Mn(Ii), Co(Ii), Cu(Ii) And Zn With 5-Amino-2-Mercaptobenzimidazole, Lobar Gapurova, Dilnoza Rakhmonova, Shakhnoza Kadirova

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this work is to study the effect of the nature of electron-donor and electron-withdrawing substituents in the molecules of heterocyclic ligands, the nature of acidoligands and transition metal ions on the properties of the synthesized coordination compounds. A method for the synthesis of new complex compounds of Mn (II), Cо (II), Cu (II) and Zn with 5-amino-2-mercaptobenzimidazole has been developed and the composition and structure of the synthesized complex compounds have been studied using modern physicochemical methods, such as elemental, thermogravimetric, X-ray phase analysis and IR spectroscopy. Coordination competing donor centers, electronic and geometric structures of the …

Modified Electrode Surfaces With Hydrogen Evolution Reaction Catalysts Derived From Electropolymerized Complexes With Redox Active Ligands., Amanda Mae Arts

Electronic Theses and Dissertations

The demand for energy is growing exponentially, and to keep up with these demands new technologies for renewable energy have received increased attention. Hydrogen is one of the most promising energy sources for the future and plays a vital role in water electrolysis and fuel cells, as the hydrogen evolution reaction (HER) is the main step in the water splitting process. To increase the reaction rate and improve efficiency for the water electrolysis, catalysts are used to minimize the overpotential.

Most of the current electrocatalysts for HER are heterogeneous in nature and are dominated by platinum and other precious metals …

Synthesis And Spectroscopic Study Of Complex Compounds Of Mn(Ii), Co(Ii), Ni(Ii), Cu(Ii) And Zn(Ii) Acetates With 2-Aminobenzimidazole, Gapurova Lobar, Kadirova Shakhnoza, Rakhmonоva Dilnoza, Olimova Manzura

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the work is to develop a synthesis procedure and obtain new complex compounds of transition metal acetates with 2-aminobenzimidazole (L), to study the composition and structure of the synthesized compounds by elemental, thermal, X-ray phase analysis and IR spectroscopy. A procedure for the synthesis of new complex compounds of Mn(II), Cо(II), Ni(II), Cu(II) and Zn acetates with 2-aminobenzimidazole was developed and the composition and structure of the synthesized complex compounds were studied using modern physicochemical methods. Coordination competing donor centers, electronic and geometric structures of the ligand molecule were studied on the basis of a quantum-chemical calculation …

Synthesis And Research Of New Heterometal Complexes Cо(Ii), Ni(Ii), Cu(Ii) And Mn(Ii) Based On V(V) And 5-(4-Pyridyl)-1,3,4-Oxadiazole-2(3h)-Thione Lubricants, Pirimova Mehribon, Kadirova Shakhnoza, Rakhmonоva Dilnoza, Ziyayev Abduhakim

CHEMISTRY AND CHEMICAL ENGINEERING

The oxadiazole derivatives complex compounds with metals are biologically active substances. The aim of the study was to study the interaction of the chlorides of Co (II), Ni (II), Cu (II) and Mn (II) with 5-(4-pyridyl)-1,3,4-oxadiazole-2(3H)–thione, ammonium vanadate. Competitive coordination of donor centers, electronic and geometric structures of the ligand molecule were studied on the basis of the quantum-chemical software package Gaussian09 LanL2DZ. It was shown that 5-(4-pyridyl)-1,3,4-oxadiazole-2(3H)-thione ligand is partially coordinated through a localized nitrogen or sulfur atoms at formation of the complex. А procedure was developed for the synthesis of new mixed-metal complexes. The composition and structure of …

Synthesis And Research Of New Heterometal Complexes Cо(Ii), Ni(Ii), Cu(Ii) And Mn(Ii) Based On V(V) And 5-(4-Pyridyl)-1,3,4-Oxadiazole-2(3h)-Thione Lubricants, Pirimova Mehribon, Kadirova Shakhnoza, Rakhmonоva Dilnoza, Ziyayev Abduhakim

CHEMISTRY AND CHEMICAL ENGINEERING

The oxadiazole derivatives complex compounds with metals are biologically active substances. The aim of the study was to study the interaction of the chlorides of Co (II), Ni (II), Cu (II) and Mn (II) with 5-(4-pyridyl)-1,3,4-oxadiazole-2(3H)–thione, ammonium vanadate. Competitive coordination of donor centers, electronic and geometric structures of the ligand molecule were studied on the basis of the quantum-chemical software package Gaussian09 LanL2DZ. It was shown that 5-(4-pyridyl)-1,3,4-oxadiazole-2(3H)-thione ligand is partially coordinated through a localized nitrogen or sulfur atoms at formation of the complex. А procedure was developed for the synthesis of new mixed-metal complexes. The composition and structure of …

Synthesis And Spectroscopic Research Coordination Compounds Of Nickel (Ii) And Copper (Ii) With Bases Of Shiff, Z.T. Karimov, S.I. Nurnazarov

Gorniy vestnik Uzbekistana

The Ligand is product of condensation salicyl aldehyde with ortho aminophenol. On the basis of the resulted Ligand, synthesed coordinated compound of Cu(II) and Ni(II). Newly synthesized complexes investigate the structural formula of IR, PR, EPR of the spectroscopic researches.

Magnetic Ordering In A Vanadium-Organic Coordination Polymer Using A Pyrrolo[2,3-D:5,4-D']Bis(Thiazole)-Based Ligand, Yulia A. Getmanenko, Christopher S. Mullins, Vladimir N. Nesterov, Stephanie Lake, Chad Risko, Ezekiel Johnston-Halperin

Chemistry Faculty Publications

Here we present the synthesis and characterization of a hybrid vanadium-organic coordination polymer with robust magnetic order, a Curie temperature T_C of ∼110 K, a coercive field of ∼5 Oe at 5 K, and a maximum mass magnetization of about half that of the benchmark ferrimagnetic vanadium(tetracyanoethylene)_~2 (V·(TCNE)_~2). This material was prepared using a new tetracyano-substituted quinoidal organic small molecule 7 based on a tricyclic heterocycle 4-hexyl-4H-pyrrolo[2,3-d:5,4-d′]bis(thiazole) (C₆-PBTz). Single crystal X-ray diffraction of the 2,6-diiodo derivative of the parent C₆-PBTz, showed a disordered hexyl chain and …

Functional Nanostructures From Nanoparticle Building Blocks, Jimmy Lawrence

Doctoral Dissertations

Advances in the synthetic strategies of engineered nanomaterials, multifunctional molecules and polymers have opened pathways for the development of functional nanomaterials having unique optoelectronic, mechanical, and biological properties. By designing the chemistry of surface ligands, the organic interface of nanoparticles, one can further the versatility and utilization of engineered nanomaterials, opening pathways for breakthroughs in sensing, catalysis, and delivery using nanomaterials. This thesis describes the synthesis and characterization of small molecule and polymer ligand functionalized inorganic nanoparticles (e.g., metal, semiconducting). Embedding specific chemical functionality into the ligand periphery of nanoparticles enables the resulting functional nanoparticles to react selectively …

Optimal Aggregation Of Fcεri With A Structurally Defined Trivalent Ligand Overrides Negative Regulation Driven By Phosphatases, Avanika Mahajan, Dipak Barua, Patrick Cutler, Diane S. Lidke, Flor A. Espinoza, Carolyn Pehlke, Rachel Grattan, Yuko Kawakami, Chang-Shung Tung, Andrew R. M. Bradbury, William S. Hlavacek, Bridget S. Wilson

Chemical and Biochemical Engineering Faculty Research & Creative Works

To investigate why responses of mast cells to antigen-induced IgE receptor (FcεRI) aggregation depend nonlinearly on antigen dose, we characterized a new artificial ligand, DF3, through complementary modeling and experimentation. This ligand is a stable trimer of peptides derived from bacteriophage T4 fibritin, each conjugated to a hapten (DNP). We found low and high doses of DF3 at which degranulation of mast cells sensitized with DNP-specific IgE is minimal, but ligand-induced receptor aggregation is comparable to aggregation at an intermediate dose, optimal for degranulation. This finding makes DF3 an ideal reagent for studying the balance of negative and positive signaling …

Factors Controlling Synthesis Of Iron Oxide Nanoparticles And The Effect Of Surface Charge On Magnetic Hyperthermia, Bin Qi

All Dissertations

ABSTRACT
Iron oxide nanoparticles (IONPs) have been widely studied in the theranostics application due to their promising magnetic properties, low cytotoxicity and attractive biocompatibility. Despite the numerous studies on the kinetic mechanisms of IONPs synthesis and thus the resulting size, shape and crystallinity; there are still considerable unsolved issues in quantitatively depicting the dependence between particle morphology and the reaction conditions.
To begin to explain some of these phenomena, the kinetic mechanism for the morphology and crystalline changes of IONPs with the ligand/precursor ratio in nanoparticle synthesis was investigated. During the synthesis of nanoparticles via thermal decomposition of iron precursors, …

Effect Of Polymer Ligand Structures On Fluorescence Of Gold Clusters Prepared By Photoreduction, Luo Li, Zhen Li, Hui Zhang, Shoucun Zhang, Irfan Majeed, Bien Tan

Australian Institute for Innovative Materials - Papers

Blue emission fluorescent Au5 clusters with maximum quantum yield of 20.1% were synthesized by a simple photoreduction method using three specially designed tridentate polymer ligands. The evolution of fluorescent Au nanoclusters (Au NCs) under UV irradiation was studied by fluorescence, UV-Vis and X-ray photoelectron spectroscopic techniques, suggesting that the fluorescence of Au NCs is size-dependent and is associated with the presence of Au(i) ions in the Au NCs. The effect of polymer structure on the fluorescent Au NCs has also been discussed. These highly fluorescent Au NCs have potential applications in the fabrication of optoelectronic devices and light emitting materials.

Tuning The Properties Of Metal-Ligand Complexes To Modify The Properties Of Supramolecular Materials, Ian Henderson

Open Access Dissertations

Supramolecular chemistry is the study of discreet molecules assembled into more complex structures though non-covalent interactions such as host-guest effects, pi-pi stacking, electrostatic effects, hydrogen bonding, and metal-ligand interactions. Using these interactions, complex hierarchical assembles can be created from relatively simple precursors.

Of the supramolecular interactions listed above, metal-ligand interactions are of particular interest due to the wide possible properties which they present. Factors such as the denticity, polarizability, steric hindrance, ligand structure, and the metal used (among others) contribute to a dramatic range in the physical properties of the metal-ligand complexes. Particularly affected by these factors are the kinetic …