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... and standing at ambient temperature. The optimized conditions (see Experimental Section for details) were used in the reactions of H2atrc with several metal salts. The use of distinct Zn2+ salts [ZnCl2, Zn(NO3)2·6H2O, ZnSO4·7H2O and Zn(ClO4)·6H2O] with H2atrc at a ratio of 0.1:0.1–0.6 mmol (with a s ...
... and standing at ambient temperature. The optimized conditions (see Experimental Section for details) were used in the reactions of H2atrc with several metal salts. The use of distinct Zn2+ salts [ZnCl2, Zn(NO3)2·6H2O, ZnSO4·7H2O and Zn(ClO4)·6H2O] with H2atrc at a ratio of 0.1:0.1–0.6 mmol (with a s ...
Angewandte Chemie : International Edition Highly
... The importance of industrial catalysis by platinum and palladium has motivated extensive studies of their gas phase chemistry.[1] Each metal atom is known to initiate cleavage of the C−H and C=C bonds of hydrocarbon precursors. The present study is believed to provide the first pure rotational spect ...
... The importance of industrial catalysis by platinum and palladium has motivated extensive studies of their gas phase chemistry.[1] Each metal atom is known to initiate cleavage of the C−H and C=C bonds of hydrocarbon precursors. The present study is believed to provide the first pure rotational spect ...
surface structural model for ferrihydrite
... prepeak of ~0.075 • 1.5 = 0.112, notably lower than the experimental one (0.141). The underestimation of the new prepeak intensity comes from a 2nd source of error, that is, the ratio of oscillator strengths between ViFe(I[I) and IVFe(I/I) species. Zhao et al. (1994) used a ratio of 1:3 determined f ...
... prepeak of ~0.075 • 1.5 = 0.112, notably lower than the experimental one (0.141). The underestimation of the new prepeak intensity comes from a 2nd source of error, that is, the ratio of oscillator strengths between ViFe(I[I) and IVFe(I/I) species. Zhao et al. (1994) used a ratio of 1:3 determined f ...
Chapter 7 - Brian Tissue Home
... (a) KMnO4(s): Mn(VII) in a covalent oxyanion, MnO4−. (b) MnCl63−(aq): Mn(III), Cl has a −1 oxidation state, and the overall complex charge is −3. (c) Mn(H2O)62+(aq): Mn(II), water is neutral, and the overall charge of this ion is +2. (d) Mn(H2O)67+(aq): Mn(VII), this complex as written does not exis ...
... (a) KMnO4(s): Mn(VII) in a covalent oxyanion, MnO4−. (b) MnCl63−(aq): Mn(III), Cl has a −1 oxidation state, and the overall complex charge is −3. (c) Mn(H2O)62+(aq): Mn(II), water is neutral, and the overall charge of this ion is +2. (d) Mn(H2O)67+(aq): Mn(VII), this complex as written does not exis ...
Ruthenium(II/III) - Publications of the IAS Fellows
... higher energy bands in the UV region are of intra-ligand p–p* type or charge-transfer transitions involving energy levels which are higher in energy than the ligand lowest unoccupied molecular orbital (LUMO). It may be noted that for the Ru(bpy) 21 complex the ...
... higher energy bands in the UV region are of intra-ligand p–p* type or charge-transfer transitions involving energy levels which are higher in energy than the ligand lowest unoccupied molecular orbital (LUMO). It may be noted that for the Ru(bpy) 21 complex the ...
Can Transition Metals and Group II Mono
... ligands feature lone pairs that repelled by the bonding electrons in the molecule, stick out prominently and are readily accessible for complexation by the metal. As can be seen in Figure 1, the complexes exhibit axial chirality. Together, the homochiral and heterochiral complexes form a diastereome ...
... ligands feature lone pairs that repelled by the bonding electrons in the molecule, stick out prominently and are readily accessible for complexation by the metal. As can be seen in Figure 1, the complexes exhibit axial chirality. Together, the homochiral and heterochiral complexes form a diastereome ...
S R (II) N-
... The study of ruthenium complexes is of high interest due to their applications in different fields of science.1 Ruthenium is a metal situated in the d group of the periodic table whose electronic configuration is [Kr] 4d75s. One relevant feature for this element together with the osmium, is the dive ...
... The study of ruthenium complexes is of high interest due to their applications in different fields of science.1 Ruthenium is a metal situated in the d group of the periodic table whose electronic configuration is [Kr] 4d75s. One relevant feature for this element together with the osmium, is the dive ...
Chemistry of vanadium-carbon single and double bonds Buijink, Jan
... Characterization of organo-vanadium complexes. The use of NMR spectroscopy, which has become the major technique for structure assignment and reactivity study in organometallic chemistry, is severely limited in organovanadium complexes by the frequently occurring paramagnetism. The 1H NMR resonances ...
... Characterization of organo-vanadium complexes. The use of NMR spectroscopy, which has become the major technique for structure assignment and reactivity study in organometallic chemistry, is severely limited in organovanadium complexes by the frequently occurring paramagnetism. The 1H NMR resonances ...
Correlated Electrons: From Models to Materials - cond
... Brillouin zone. The main source of complex correlated behavior of electronic systems, related with strong fluctuations between different low-energy fermionic configurations, is shown schematically in Fig. 2. For example, if the free energy of an electronic system has only one well defined minimum at ...
... Brillouin zone. The main source of complex correlated behavior of electronic systems, related with strong fluctuations between different low-energy fermionic configurations, is shown schematically in Fig. 2. For example, if the free energy of an electronic system has only one well defined minimum at ...
Electron attachment to molecular clusters by collisional charge transfer
... A) were observed, but extensive signal averaging was required to detect any other positive ion species (for which typical signals are E A). Thus,here we present only observations of negative ions. As seen in Figure 2, the chlorine cluster system yields negative ions corresponding to electron attachm ...
... A) were observed, but extensive signal averaging was required to detect any other positive ion species (for which typical signals are E A). Thus,here we present only observations of negative ions. As seen in Figure 2, the chlorine cluster system yields negative ions corresponding to electron attachm ...
Received 02-11-2001
... °C. No separate weight loss that can be attributed to the loss of coordinated water was observed probably because of the weak interaction of the water molecules and the metal ions in these complexes. The TGA and the DSC data indicate that all of the complexes isolated are unstable and decomposes in ...
... °C. No separate weight loss that can be attributed to the loss of coordinated water was observed probably because of the weak interaction of the water molecules and the metal ions in these complexes. The TGA and the DSC data indicate that all of the complexes isolated are unstable and decomposes in ...
transition metal complexes possessing tunable and switchable
... MLCT bands, whilst 21–24 display single bands and 25–31 also show apparently single bands which are composed of multiple transitions. Cyclic voltammetric studies show that the Ru-based HOMO energy is only slightly sensitive to changes in the structure of the pyridinium ligands, but the LUMO energies ...
... MLCT bands, whilst 21–24 display single bands and 25–31 also show apparently single bands which are composed of multiple transitions. Cyclic voltammetric studies show that the Ru-based HOMO energy is only slightly sensitive to changes in the structure of the pyridinium ligands, but the LUMO energies ...
and Square-Grooved Networks to Tubular Assemblies in
... ions are both chelated by three carboxylate groups, with unexceptional U–O(oxo) [1.758(4)–1.779(5) Å, average 1.771(8) Å] and U–O(carboxylate) [2.422(4)–2.498(5) Å, average 2.46(2) Å] bond lengths (Figs. 4 and S2, Supporting Information). The unique lead(II) cation is chelated by the bipy molecule [ ...
... ions are both chelated by three carboxylate groups, with unexceptional U–O(oxo) [1.758(4)–1.779(5) Å, average 1.771(8) Å] and U–O(carboxylate) [2.422(4)–2.498(5) Å, average 2.46(2) Å] bond lengths (Figs. 4 and S2, Supporting Information). The unique lead(II) cation is chelated by the bipy molecule [ ...
chemistry - Textbooks Online
... Where has chemistry come from ? Throughout the history of the human race, people have struggled to make sense of the world around them. Through the branch of science we call chemistry we have gained an understanding of the matter which makes up our world and of the interactions between particles on ...
... Where has chemistry come from ? Throughout the history of the human race, people have struggled to make sense of the world around them. Through the branch of science we call chemistry we have gained an understanding of the matter which makes up our world and of the interactions between particles on ...
Oxidative Additions of Aryl Halides to Palladium Proceed through
... there is no direct experimental evidence to support the calculations. Kinetic studies suggest the identity of the halide is critical, with iodo- and bromobenzenes reacting with PdL2 and chlorobenzenes with PdL.[25] However, it is difficult if not impossible to unambiguously isolate the highly reacti ...
... there is no direct experimental evidence to support the calculations. Kinetic studies suggest the identity of the halide is critical, with iodo- and bromobenzenes reacting with PdL2 and chlorobenzenes with PdL.[25] However, it is difficult if not impossible to unambiguously isolate the highly reacti ...
Synthesis, characterization and spectroscopic investigation
... Miniflex diffractometer using Cu Ka radiation (30 kV and 15 mA) from 21 to 901 and 1 s of pass time. Infrared spectra were recorded in KBr pellets on a Bomen model MB-102 spectrophotometer in the range from 350 to 4000 cm 1, to obtain information on ligand-Tm3 + coordination. In addition, near-infr ...
... Miniflex diffractometer using Cu Ka radiation (30 kV and 15 mA) from 21 to 901 and 1 s of pass time. Infrared spectra were recorded in KBr pellets on a Bomen model MB-102 spectrophotometer in the range from 350 to 4000 cm 1, to obtain information on ligand-Tm3 + coordination. In addition, near-infr ...
Naphthalene adsorptions on graphene using Cr/Cr2/Fe/Fe2 linkages
... A (4 × 4) supercell of graphene containing 32 carbon atoms is employed to host the M–Np and M2 –Np complexes. The chosen graphene cell is wide enough to avoid possible interactions between the attached complexes due to periodic boundary conditions. In the first part, the periodic graphene sheet is de ...
... A (4 × 4) supercell of graphene containing 32 carbon atoms is employed to host the M–Np and M2 –Np complexes. The chosen graphene cell is wide enough to avoid possible interactions between the attached complexes due to periodic boundary conditions. In the first part, the periodic graphene sheet is de ...
Werner`s coordination theory
... Werner's theory and isomerism Werner was able to prdict the geometry of a complesx on the basis of no. of isomers synthesized without having the access to modern X-ray diffraction tools etc. For [Co(NH3)4Cl2]Cl which has a coordination no. 6 , three geometries are possible 1.Planar hexagon, which wo ...
... Werner's theory and isomerism Werner was able to prdict the geometry of a complesx on the basis of no. of isomers synthesized without having the access to modern X-ray diffraction tools etc. For [Co(NH3)4Cl2]Cl which has a coordination no. 6 , three geometries are possible 1.Planar hexagon, which wo ...
Chem. Eur. J. 11, 5227-5237
... modynamic approach, proposed by Ercolani for the quantitative characterisation of multicomponent assemblies involving metals and ligands in supramolecular complexes, gives a new insight into some reliable assessments of cooperativity and repetitive statistical binding in these systems.[3] In his mod ...
... modynamic approach, proposed by Ercolani for the quantitative characterisation of multicomponent assemblies involving metals and ligands in supramolecular complexes, gives a new insight into some reliable assessments of cooperativity and repetitive statistical binding in these systems.[3] In his mod ...
The Career of Harry B. Gray
... In photosynthetic reaction center (PRC), primary ET rate is same over large temperature range" Cooling from 300K to 4K, primary ET rate increases by a factor of 3" ...
... In photosynthetic reaction center (PRC), primary ET rate is same over large temperature range" Cooling from 300K to 4K, primary ET rate increases by a factor of 3" ...
Synthesis, characterisation and antimicrobial studies on La(III), Ce(III
... Azo-methine nitrogen to the metal ion [26-28]. The absorption bands appearing in the 1540 - 1560 cm-1 region in the complexes are attributed to the ٧ (C=C) vibration. The absorption bands appearing in the 2935-2920 cm-1 region in the complexes is due to ٧(C-H) vibrations. The ٧(OH) vibration of the ...
... Azo-methine nitrogen to the metal ion [26-28]. The absorption bands appearing in the 1540 - 1560 cm-1 region in the complexes are attributed to the ٧ (C=C) vibration. The absorption bands appearing in the 2935-2920 cm-1 region in the complexes is due to ٧(C-H) vibrations. The ٧(OH) vibration of the ...
Jahn–Teller effect
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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.