Paramagnetic Metal Complexes as Water Proton
... are thought to induce distortions from octahedral symmetry that, in turn, lead to transient zero-field splitting (ZFS) of the electronic spin levels. Electronic relaxation occurs as a result of this ZFS modulation, with T1C1 given by eq 8, where the constant B is related to the r ...
... are thought to induce distortions from octahedral symmetry that, in turn, lead to transient zero-field splitting (ZFS) of the electronic spin levels. Electronic relaxation occurs as a result of this ZFS modulation, with T1C1 given by eq 8, where the constant B is related to the r ...
Full text - University of Amsterdam
... chemical compounds – so called libraries – that can be screened efficiently for the identification of useful compounds. Supramolecular chemistry focuses on the non-covalent bonding interactions of molecules. Important concepts that have been demonstrated by this type of chemistry include host-guest ...
... chemical compounds – so called libraries – that can be screened efficiently for the identification of useful compounds. Supramolecular chemistry focuses on the non-covalent bonding interactions of molecules. Important concepts that have been demonstrated by this type of chemistry include host-guest ...
university of oslo
... overview and ability to analyse a situation may be obscured or lost. The newcomer may find the field difficult to enter. Along with the developments of theory and modelling, the field has changed focus from binary oxides to ternary or higher oxides. This is much due to the growing awareness that per ...
... overview and ability to analyse a situation may be obscured or lost. The newcomer may find the field difficult to enter. Along with the developments of theory and modelling, the field has changed focus from binary oxides to ternary or higher oxides. This is much due to the growing awareness that per ...
Lithium, Sodium and Potassium Magnesiate Chemistry: A Structural
... Figure 12: Molecular structure of (THF)LiMgnBuR* 17 Two halide containing amido lithium magnesiates (THF)3LiMg(TMP)Cl2 18 (Figure 13)24 and the dimeric [(THF)2LiMg(NiPr2)Cl2]2 19 (Figure 14)25 have recently been reported. These are of particular importance to the well-developed synthetic area of tur ...
... Figure 12: Molecular structure of (THF)LiMgnBuR* 17 Two halide containing amido lithium magnesiates (THF)3LiMg(TMP)Cl2 18 (Figure 13)24 and the dimeric [(THF)2LiMg(NiPr2)Cl2]2 19 (Figure 14)25 have recently been reported. These are of particular importance to the well-developed synthetic area of tur ...
Study on Synthesis and Antibacterial Activity of Co(II) and NiC(II
... hence the complexes are spin free with octahedral stereochemistry(18). The magnetic moments of Ni(II) complexes calculated also from the corrected magnetic susceptibilities are in the range 2.75–2.79B.M as shown in (Table 1), indicating octahedral geometry around the nickel ion(19). The coordination ...
... hence the complexes are spin free with octahedral stereochemistry(18). The magnetic moments of Ni(II) complexes calculated also from the corrected magnetic susceptibilities are in the range 2.75–2.79B.M as shown in (Table 1), indicating octahedral geometry around the nickel ion(19). The coordination ...
Corynebactin and Enterobactin: Related Siderophores of Opposite
... The major role of siderophores in microbial iron transport and bacterial pathogenicity is now well established.1 These low molecular weight chelators are expressed to overcome the insolubility of Fe3+ at pH 7 (∼10-18 M).2 The ferric complexes enter the bacterial cell via specific receptor proteins o ...
... The major role of siderophores in microbial iron transport and bacterial pathogenicity is now well established.1 These low molecular weight chelators are expressed to overcome the insolubility of Fe3+ at pH 7 (∼10-18 M).2 The ferric complexes enter the bacterial cell via specific receptor proteins o ...
Inorganic Molecular Capsules: From Structure to
... challenging areas of chemical nanoscience. These high-symmetry capsules are invariably comprised of many metal–ligand components, which often selfassemble rapidly and in high yield into a single gigantic species—sometimes even protein-sized.[1] However, the interest in these systems goes far beyond ...
... challenging areas of chemical nanoscience. These high-symmetry capsules are invariably comprised of many metal–ligand components, which often selfassemble rapidly and in high yield into a single gigantic species—sometimes even protein-sized.[1] However, the interest in these systems goes far beyond ...
A Chapter 4 Organometallics
... H-atoms in g position with respect to U: this is called a g-agostic interaction. Therefore, the coordination number is larger than 3 in this compound and this is often the case for lowCN organometallic compounds MSc: f-Elements, Prof. J.-C. Bünzli, 2008 ...
... H-atoms in g position with respect to U: this is called a g-agostic interaction. Therefore, the coordination number is larger than 3 in this compound and this is often the case for lowCN organometallic compounds MSc: f-Elements, Prof. J.-C. Bünzli, 2008 ...
Metal Complexes as Antimicrobial Agents
... and Grisofluvine were used as reference compounds for antbacterial and antifungal activities, respectively. Escherichia coli, Salmonella typhi, Staphylococcus aureus and Bacillus subtillus (bacteria) or Aspergillus terreus and Aspergillus flavus (Fungi) were used as the test organisms. Results have ...
... and Grisofluvine were used as reference compounds for antbacterial and antifungal activities, respectively. Escherichia coli, Salmonella typhi, Staphylococcus aureus and Bacillus subtillus (bacteria) or Aspergillus terreus and Aspergillus flavus (Fungi) were used as the test organisms. Results have ...
Solubility and complexes
... Stereoisomers: same atom connectivities but different arrangement of atoms in space Geometric isomerism Optical isomerism ...
... Stereoisomers: same atom connectivities but different arrangement of atoms in space Geometric isomerism Optical isomerism ...
Complex defects
... catalysts, etc). Computer modelling now enables detailed analysis of defect chemistry and transport processes, and helps us interpret experimental, see systematic correlations, and predict new and improved materials. Although the increasing accuracy and complexity is welcome and necessary, the simpl ...
... catalysts, etc). Computer modelling now enables detailed analysis of defect chemistry and transport processes, and helps us interpret experimental, see systematic correlations, and predict new and improved materials. Although the increasing accuracy and complexity is welcome and necessary, the simpl ...
METAL IONS IN LIFE SCIENCES
... structures in this field concern to cytosine and 1-substituted cytosine ligands. The compound {[Cd(μ2Cl)2(H2O)2]·2Hcyt}n [28] is a cytosine solvate of a polymeric complex where the metal is sixcoordinated. In the crystal of this compound, there is a H-bonded chain of Hcyt molecules built by two pair ...
... structures in this field concern to cytosine and 1-substituted cytosine ligands. The compound {[Cd(μ2Cl)2(H2O)2]·2Hcyt}n [28] is a cytosine solvate of a polymeric complex where the metal is sixcoordinated. In the crystal of this compound, there is a H-bonded chain of Hcyt molecules built by two pair ...
Determining the size-dependent structure of ligand-free gold
... on a DC magnetron sputtering device (Cuomo & Rossnagel 1986; Hahn & Averback 1990). The source comprises a DC sputter head in a liquid-nitrogencooled aggregation tube filled with a mixture of Ar and He (approx. 1 : 10) to a pressure of approximately 1 mbar. Energetic argon ions generated in the plasm ...
... on a DC magnetron sputtering device (Cuomo & Rossnagel 1986; Hahn & Averback 1990). The source comprises a DC sputter head in a liquid-nitrogencooled aggregation tube filled with a mixture of Ar and He (approx. 1 : 10) to a pressure of approximately 1 mbar. Energetic argon ions generated in the plasm ...
Lecture 11 – Reaction Types and Mechanisms for
... because the CFSE is so much greater for octahedral coordination than the CFSE than any possible geometry in 5- or 7-coordination. The loss in CFSE on going from 6-coordination to 5- or 7-coordination increases the activation energy for the reaction, thus slowing it. ...
... because the CFSE is so much greater for octahedral coordination than the CFSE than any possible geometry in 5- or 7-coordination. The loss in CFSE on going from 6-coordination to 5- or 7-coordination increases the activation energy for the reaction, thus slowing it. ...
atomic and molecular physics using positron traps
... energies (e.g., positron energies below the threshold for positronium formation). There have been extensive studies of positron annihilation on atoms and molecules in work spanning several decades [5, 8, 9]. Typically these experiments were conducted by injecting fast positrons into gases at pressur ...
... energies (e.g., positron energies below the threshold for positronium formation). There have been extensive studies of positron annihilation on atoms and molecules in work spanning several decades [5, 8, 9]. Typically these experiments were conducted by injecting fast positrons into gases at pressur ...
d-Block Elements
... Hence nearly all the transition elements display typical metallic properties such as high tensile strength, ductility, malleability, high thermal and electrical conductivity and metallic lustre. With the exceptions of Zn,Cd, Hg and Mn, they have one or more typical metallic structures at normal temp ...
... Hence nearly all the transition elements display typical metallic properties such as high tensile strength, ductility, malleability, high thermal and electrical conductivity and metallic lustre. With the exceptions of Zn,Cd, Hg and Mn, they have one or more typical metallic structures at normal temp ...
Comparison of structurally-related alkoxide, amine, and thiolate
... substrate binding site, contribute significantly to the catalyst’s function by dramatically lowering the Fe–O stretching frequency (mFe–O = 419 cm!1) and force constant (k = 1.20 mdynes/cm) well-below that of any other reported iron-peroxo, thereby favoring Fe–O bond cleavage and H2O2 release [24]. ...
... substrate binding site, contribute significantly to the catalyst’s function by dramatically lowering the Fe–O stretching frequency (mFe–O = 419 cm!1) and force constant (k = 1.20 mdynes/cm) well-below that of any other reported iron-peroxo, thereby favoring Fe–O bond cleavage and H2O2 release [24]. ...
A-Frame Complexes of Dirhodium Bridged by Dicarbene and
... properties like those of trialkylphosphines3 and may actually be better donors than phosphines.4 However, NHC’s are not merely phosphine substitutes; they offer a useful steric alternative to phosphines in having a very different shape. While phosphines are often described as conical,5 NHC ligands a ...
... properties like those of trialkylphosphines3 and may actually be better donors than phosphines.4 However, NHC’s are not merely phosphine substitutes; they offer a useful steric alternative to phosphines in having a very different shape. While phosphines are often described as conical,5 NHC ligands a ...
Excitation Transfer between Conjugated Polyelectrolytes and
... metal complexes. The heavy central metal atom leads to a strong mixing of the excited singlet and triplet states by spin-orbit coupling. This leads to triplet emission with high efficiency and long-lived excited states. The combination of a transition metal ion and organic ligands gives rise not onl ...
... metal complexes. The heavy central metal atom leads to a strong mixing of the excited singlet and triplet states by spin-orbit coupling. This leads to triplet emission with high efficiency and long-lived excited states. The combination of a transition metal ion and organic ligands gives rise not onl ...
The theory of electron transfer
... development of the field has been aided by contributions from some of the finest minds in science. However, despite its long and intriguing history, I have made no attempt in the present work to summarize the complex interplay of all the various theories that have been suggested at one time or anoth ...
... development of the field has been aided by contributions from some of the finest minds in science. However, despite its long and intriguing history, I have made no attempt in the present work to summarize the complex interplay of all the various theories that have been suggested at one time or anoth ...
lecture 5 ligand substitution
... trans influence and trans effect • In square planar complexes, some ligands direct substitution to a position trans to themselves. • When reaction is controlled by factors influencing the ground state energy of the complex – trans influence • Reaction is controlled by factors affecting the transiti ...
... trans influence and trans effect • In square planar complexes, some ligands direct substitution to a position trans to themselves. • When reaction is controlled by factors influencing the ground state energy of the complex – trans influence • Reaction is controlled by factors affecting the transiti ...
Evolving Structural Diversity and Metallicity in Compressed Lithium
... phases). The first thought on finding a structure featuring N2 molecules (albeit that they are slightly reduced) and Li chains is that the ionic LiN3 is trying to dissociate to N2(s) and Li(s). Is there a driving mechanism for such a reaction? The calculated heat of formation (ΔHf) of the lithium azid ...
... phases). The first thought on finding a structure featuring N2 molecules (albeit that they are slightly reduced) and Li chains is that the ionic LiN3 is trying to dissociate to N2(s) and Li(s). Is there a driving mechanism for such a reaction? The calculated heat of formation (ΔHf) of the lithium azid ...
Anisotropy of Elastic Behavior
... • Different crystal systems can be characterized exclusively by their symmetries. Table 7-1 presents the different symmetry operations defining the seven crystal systems. • The seven crystalline systems can be perfectly described by their axes of rotation. For example, a threefold rotation is a rota ...
... • Different crystal systems can be characterized exclusively by their symmetries. Table 7-1 presents the different symmetry operations defining the seven crystal systems. • The seven crystalline systems can be perfectly described by their axes of rotation. For example, a threefold rotation is a rota ...
Jahn–Teller effect
The Jahn–Teller effect, sometimes also known as Jahn–Teller distortion, describes the geometrical distortion of molecules and ions that is associated with certain electron configurations. This electronic effect is named after Hermann Arthur Jahn and Edward Teller, who proved, using group theory, that orbital nonlinear spatially degenerate molecules cannot be stable. The Jahn–Teller theorem essentially states that any nonlinear molecule with a spatially degenerate electronic ground state will undergo a geometrical distortion that removes that degeneracy, because the distortion lowers the overall energy of the species. For a description of another type of geometrical distortion that occurs in crystals with substitutional impurities see article off-center ions.