K‐Ion Battery Cathode Design Utilizing Trigonal Prismatic Ligand Field

ESR spectra of thianatocopper(II) complexes with imidazole derivatives were studied in ethanolic solutions at 295 and 123 K. Axialsymmetric spectra, attributed to the monomeric complex units, were obtained for the frozen solutions. The bonding parameters were interpreted by using calculated g, Cu-hyperfine, and 14N-ligand hyperfine splitting values. The Cu-N bond parameters indicate a considerable delocalization of the unpaired electron. The values of the isotropic Cu-hyperfine splitting suggest that the deviations from the planar symmetry of the CuN4 units are due to tetrahedral perturbation of the ligand field.

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Niobocene Dichloride and Niobocene Diiodide: Electronic Absorption Spectra and Electron Spin Resonance

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19980628 ◽

1998 ◽

Vol 63 (5) ◽

pp. 628-635 ◽

Cited By ~ 1

Author(s):

Jana Holubová ◽

Zdeněk Černošek ◽

Ivan Pavlík

Keyword(s):

Absorption Spectra ◽

Electronic Absorption ◽

Electronic Absorption Spectra ◽

Point Group ◽

Esr Spectra ◽

Ligand Field ◽

Orbital Interaction ◽

Symmetry Point Group ◽

Spin Orbital ◽

Halide Ligands

The effect of the halide ligand on the bonding of niobium in niobocene dichloride and niobocene diiodide was investigated. The electronic absorption spectra of the two compounds in the range of d-d transitions were resolved into four bands corresponding to transitions of the d1 electron between five frontier orbitals in a molecule of symmetry point group C2v. The energies of the frontier molecular orbitals were determined relatively to the energy of the orbitals in the spherically symmetric ligand field formed by the appropriate halide ligands. The effect of the halide ligands on the spin-orbital interaction of the HOMO orbital is discussed qualitatively on the basis the ESR spectra.

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The Character of Low-Lying Excited States of Mixed-Ligand Metal Carbonyls. TD-DFT and CASSCF/CASPT2 Study of [W(CO)4L] (L = ethylenediamine, N,N'-dialkyl-1,4-diazabutadiene) and [W(CO)5L] (L = pyridine, 4-cyanopyridine)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20030089 ◽

2003 ◽

Vol 68 (1) ◽

pp. 89-104 ◽

Cited By ~ 6

Author(s):

Stanislav Záliš ◽

Antonín Vlček ◽

Chantal Daniel

Keyword(s):

Excited States ◽

Substitution Effect ◽

Electronic Transitions ◽

Ligand Field ◽

Metal Carbonyls ◽

Electron Density Redistribution ◽

Time Resolved ◽

Model Complex ◽

Td Dft ◽

Time Resolved Infrared Spectroscopy

This contribution presents the results of the TD-DFT and CASSCF/CASPT2 calculations on [W(CO)4(MeDAB)] (MeDAB = N,N'-dimethyl-1,4-diazabutadiene), [W(CO)4(en)] (en = ethylenediamine), [W(CO)5(py)] (py = pyridine) and [W(CO)5(CNpy)] (CNpy = 4-cyanopyridine) complexes. Contrary to the textbook interpretation, calculations on the model complex [W(CO)4(MeDAB)] and [W(CO)5(CNpy)] show that the lowest W→MeDAB and W→CNpy MLCT excited states are immediately followed in energy by several W→CO MLCT states, instead of ligand-field (LF) states. The lowest-lying excited states of [W(CO)4(en)] system were characterized as W(COeq)2→COax CT excitations, which involve a remarkable electron density redistribution between axial and equatorial CO ligands. [W(CO)5(py)] possesses closely-lying W→CO and W→py MLCT excited states. The calculated energies of these states are sensitive to the computational methodology used and can be easily influenced by a substitution effect. The calculated shifts of [W(CO)4(en)] stretching CO frequencies due to excitation are in agreement with picosecond time-resolved infrared spectroscopy experiments and confirm the occurrence of low-lying M→CO MLCT transitions. No LF electronic transitions were found for either of the complexes studied in the region up to 4 eV.

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The Coordination Chemistry of Phosphoryl Compounds Containing the — N(CH3)2 Group, Part VIII

Zeitschrift für Naturforschung B ◽

10.1515/znb-1972-0706 ◽

1972 ◽

Vol 27 (7) ◽

pp. 759-763 ◽

Cited By ~ 11

Author(s):

M. W. G. De Bolster ◽

W. L. Groeneveld

Keyword(s):

Coordination Chemistry ◽

General Formula ◽

Ligand Field ◽

Chemical Analyses ◽

X Ray ◽

Physical Measurements ◽

Ligand Field Spectra ◽

Chloride Adduct ◽

Ligand Field Parameters ◽

Group Part

A number of new solvates and adducts containing bisphenyldimethylaminophosphine oxide is reported. The solvates have the general formula M[(C6H5)2P(O)N(CH3)2]42+(anion-)2, in which M = Mg, Ca, Mn, Fe, Co, Ni, Cu, Zn and Cd, and the anions are ClO4- and BF4-. The adducts have the general formula M[(C6H5)2P(O)N(CH3)2]2Cl2, where M stands for the same series of metals.The compounds are characterized and identified by chemical analyses and physical measurements.Ligand-field and vibrational spectra have been investigated; values for the ligand-field parameters are reported. It is concluded that coordination takes place via the oxygen atom of the ligand.X-ray powder patterns were used in combination with ligand-field spectra to deduce the coordination around the metal ions.The interesting behaviour of the nickel (II) chloride adduct upon heating is discussed and it is shown that both a square pyramidal and a tetrahedral modification exists.

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Ligand Field Parameters

Israel Journal of Chemistry ◽

10.1002/ijch.197600035 ◽

1976 ◽

Vol 15 (3-4) ◽

pp. 189-199 ◽

Cited By ~ 9

Author(s):

Ivano Bertini ◽

Dante Gatteschi ◽

Andrea Scozzafava

Keyword(s):

Ligand Field ◽

Ligand Field Parameters

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Rational Cathode Design for High‐Power Sodium‐Metal Chloride Batteries

Advanced Functional Materials ◽

10.1002/adfm.202106367 ◽

2021 ◽

pp. 2106367

Author(s):

Gustav Graeber ◽

Daniel Landmann ◽

Enea Svaluto‐Ferro ◽

Fabrizio Vagliani ◽

Diego Basso ◽

...

Keyword(s):

High Power ◽

Metal Chloride ◽

Sodium Metal ◽

Cathode Design

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Hexagonal-Shaped Spin Crossover Nanoparticles Studied by Ising-Like Model Solved by Local Mean Field Approximation

Magnetochemistry ◽

10.3390/magnetochemistry7050069 ◽

2021 ◽

Vol 7 (5) ◽

pp. 69

Author(s):

Catherine Cazelles ◽

Jorge Linares ◽

Mamadou Ndiaye ◽

Pierre-Richard Dahoo ◽

Kamel Boukheddaden

Keyword(s):

Spin Crossover ◽

Hexagonal Lattice ◽

Mean Field ◽

Field Approximation ◽

Mean Field Approximation ◽

Ligand Field ◽

Order And Disorder ◽

The Matrix ◽

Local Mean ◽

Parameter Values

The properties of spin crossover (SCO) nanoparticles were studied for five 2D hexagonal lattice structures of increasing sizes embedded in a matrix, thus affecting the thermal properties of the SCO region. These effects were modeled using the Ising-like model in the framework of local mean field approximation (LMFA). The systematic combined effect of the different types of couplings, consisting of (i) bulk short- and long-range interactions and (ii) edge and corner interactions at the surface mediated by the matrix environment, were investigated by using parameter values typical of SCO complexes. Gradual two and three hysteretic transition curves from the LS to HS states were obtained. The results were interpreted in terms of the competition between the structure-dependent order and disorder temperatures (TO.D.) of internal coupling origin and the ligand field-dependent equilibrium temperatures (Teq) of external origin.

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Correlating Axial and Equatorial Ligand Field Effects to the Single-Molecule Magnet Performances of a Family of Dysprosium Bis-Methanediide Complexes

Chemical Science ◽

10.1039/d1sc00238d ◽

2021 ◽

Author(s):

Lewis Thomas-Hargreaves ◽

Marcus Giansiracusa ◽

Matthew Gregson ◽

Emanuele Zanda ◽

Felix O'Donnell ◽

...

Keyword(s):

Alkali Metal ◽

Single Molecule ◽

Ligand Field ◽

Single Molecule Magnet ◽

Field Effects ◽

Equatorial Ligand ◽

Metal Alkyls

Treatment of the new methanediide-methanide complex [Dy(SCS)(SCSH)(THF)] (1Dy, SCS = {C(PPh2S)2}2-) with alkali metal alkyls and auxillary ethers produces the bis-methanediide complexes [Dy(SCS)2][Dy(SCS)2(K(DME)2)2] (2Dy), [Dy(SCS)2][Na(DME)3] (3Dy) and [Dy(SCS)2][K(2,2,2-cryptand)] (4Dy). For...

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