Disubstituted derivatives of (L—L)Fe2(CO)6 (L—L = fluorocarbon bridged ligand)

1976 ◽  
Vol 54 (20) ◽  
pp. 3185-3191 ◽  
Author(s):  
Lian Sai Chia ◽  
William R. Cullen ◽  
John R. Sams ◽  
James C. Scott
Keyword(s):  
Iron Atom ◽  
Spectroscopic Studies ◽  
The Other ◽  
Bidentate Ligands ◽  
Mössbauer Measurements ◽  
Derivatives Of

The complexes (L—L)Fe2(CO)6 react with a range of bidentate ligands to give the complexes (L—L)′(L—L)Fe2(CO)4 ((L—L) = fluorocarbon-bridged ligand such as f4fars, f4AsP etc. (L—L)′ = fluorocarbon- and hydrocarbon-bridged ligands such as f4AsP diars etc.). Spectroscopic studies, in particular magnetically perturbed Mössbauer measurements, indicate that (L—L)′ in most complexes is chelated to one iron atom, FeA. This leaves one CO group on FeAcis to the FeA—FeB bond and three on FeB. A smaller class of derivatives appear to have (L—L)′ bridging the two iron atoms cis to the FeA—FeB bond. The sign of Vzz is positive at both iron sites in the bridged derivatives. It is negative at FeA and positive at FeB in the other complexes.

Structural and spectroscopic studies of transition metal nitrite complexes. X. Crystal structures of cis-Bis(2,2'-bipyridine)(nitrito-O,O')nickel(II) nitrate and hydrated Tris(2,2'-bipyridine)nickel(II) nitrite/nitrate and sulfate. Stereochemistry of the [M(bidentate ligand)2(bidentate ligand')1] system

1981 ◽  
Vol 34 (10) ◽  
pp. 2177 ◽  
Author(s):  
AJ Finney ◽  
MA Hitchman ◽  
DL Kepert ◽  
CL Raston ◽  
GL Rowbottom ◽  
...  
Keyword(s):  
Transition Metal ◽  
Crystal Structures ◽  
Coordination Sphere ◽  
Nickel Atom ◽  
Spectroscopic Studies ◽  
Bidentate Ligand ◽  
The Other ◽  
Bidentate Ligands ◽  
Nitrite Nitrate ◽  
Oxygen Atoms

The crystal structures of the title compounds are reported. In all cases, the coordination sphere of the nickel atom comprises three bidentate ligands. In (1), [Ni(bpy)2(O2N)] NO3, (Ni-N) is 2.M2 � although there are small differences between those nitrogen atoms trans to the nitrite oxygen atoms and the other two. (Ni-O) is 2.12 �. In (2), [Ni(bpy)3] NO2/NO3,xH2O, and (3), [Ni(bpy)3]- SO4,7.5H2O, a redetermination, Ni-N is shown to be c. 2.09 �; serious disorder is present among the non-cationic components of (2), precluding a definite assignment of stoichiometry.

Thio derivatives of β-diketones and their metal chelates. X. The anomalous paramagnetism of some iron(III) chelates of monothio-β-diketones

1968 ◽  
Vol 21 (8) ◽  
pp. 1987 ◽  
Author(s):  
RKY Ho ◽  
SE Livingstone
Keyword(s):  
Iron Atom ◽  
Thermal Equilibrium ◽  
Room Temperature ◽  
Magnetic Behaviour ◽  
The Other ◽  
Ligand Field ◽  
Pairing Energy ◽  
Temperature Dependent ◽  
Magnetic Susceptibilities ◽  
Derivatives Of

The magnetic susceptibilities of the iron(111) chelates Fe(R1CS=CHCOR2)3 (R1 = Ph, p-MeC6H4, p-MeOC6H4, p-BrC6H4, 2-thienyl, 2-furyl, R2 = CF3; R1 = Ph, R2 = Ph, OEt) have been investigated over a temperature range. The iron(111) complex of ethyl thiobenzoylacetate (R1 = Ph, R2 = OEt) is of the high-spin type and obeys the Curie-Weiss law with θ =-8�k. The moments of the other complexes vary between 2.31 and 6.61 B.M. at room temperature and are temperature-dependent, ranging from 1.86 to 4.07 B.M. at 80�k, depending on the nature of R1 and R2 This behaviour is postulated to be due to a thermal equilibrium between the nearly equi-energetic spin-paired (t5/2g) and spin-free (t3/2ge2/g) configurations of the iron atom, resulting from the approximately equal magnitudes of the ligand field (Δ) and the pairing energy (π) in these complexes. The ligand field and consequently the magnetic behaviour are sensitive to the nature of R1 and R2: electron-withdrawing groups appear to be the most effective in increasing the population of the spin-paired configuration.

Monosubstituted Derivatives of (L–L)Fe2(CO)6 (L–L = fluorocarbon bridged ligand)

1975 ◽  
Vol 53 (15) ◽  
pp. 2232-2239 ◽  
Author(s):  
Lian Sai Chia ◽  
William R. Cullen ◽  
John R. Sams ◽  
James C. Scott
Keyword(s):  
Mössbauer Spectra ◽  
Spectroscopic Studies ◽  
Bidentate Ligands ◽  
Group V ◽  
Mossbauer Spectra ◽  
First Time ◽  
Derivatives Of

The reaction of the ditertiary arsines and phosphines fnfars, fnfos, and fnAsP, (L–L), with Fe(CO)5 at 150° is a superior route to the complexes (L–L)Fe2(CO)6. Two are reported for the first time (L–L = f6fars, f8fars). The complexes react with monodentate and certain potentially bidentate ligands on u.v. irradiation to afford the monosubstituted derivatives L(L–L)Fe2(CO)5 and (L–L)'(L–L)Fe2(CO)5. Spectroscopic studies, in particular magnetically perturbed Mössbauer spectra, indicate that the site of substitution is trans to the FeA—FeB bond and cis to the two group V atoms (on FeA). Disubstitution seems to result in further displacement of CO from either FeA or FeB.

Energy Approximation

2017 ◽  
Author(s):  
Philip Isett
Keyword(s):  
Main Lemma ◽  
The Other ◽  
Coarse Scale ◽  
Continuous Solutions ◽  
Material Derivative ◽  
Energy Variation ◽  
Energy Approximation ◽  
The Difference ◽  
Derivatives Of

This chapter presents the equations and calculations for energy approximation. It establishes the estimates (261) and (262) of the Main Lemma (10.1) for continuous solutions; these estimates state that we are able to accurately prescribe the energy that the correction adds to the solution, as well as bound the difference between the time derivatives of these two quantities. The chapter also introduces the proposition for prescribing energy, followed by the relevant computations. Each integral contributing to the other term can be estimated. Another proposition for estimating control over the rate of energy variation is given. Finally, the coarse scale material derivative is considered.

ChemInform Abstract: SYNTHESIS AND MOESSBAUER SPECTROSCOPIC STUDIES OF CARBONYL DERIVATIVES OF (PHTHALOCYANINATO)IRON(II)

1982 ◽  
Vol 13 (36) ◽  
Author(s):  
F. CALDERAZZO ◽  
S. FREDIANI ◽  
B. R. JAMES ◽  
G. PAMPALONI ◽  
K. J. REIMER ◽  
...  
Keyword(s):  
Spectroscopic Studies ◽  
Carbonyl Derivatives ◽  
Derivatives Of

scholarly journals Voigt Transform and Umbral Image

2020 ◽  
Vol 25 (3) ◽  
pp. 49
Author(s):  
Silvia Licciardi ◽  
Rosa Maria Pidatella ◽  
Marcello Artioli ◽  
Giuseppe Dattoli
Keyword(s):  
Spectroscopic Studies ◽  
Higher Order ◽  
Point Of View ◽  
The Other ◽  
Pivotal Role ◽  
Umbral Calculus ◽  
Laguerre Functions ◽  
Hermite And Laguerre Functions ◽  
Higher Order Functions ◽  
Voigt Function

In this paper, we show that the use of methods of an operational nature, such as umbral calculus, allows achieving a double target: on one side, the study of the Voigt function, which plays a pivotal role in spectroscopic studies and in other applications, according to a new point of view, and on the other, the introduction of a Voigt transform and its possible use. Furthermore, by the same method, we point out that the Hermite and Laguerre functions, extension of the corresponding polynomials to negative and/or real indices, can be expressed through a definition in a straightforward and unified fashion. It is illustrated how the techniques that we are going to suggest provide an easy derivation of the relevant properties along with generalizations to higher order functions.

scholarly journals II. Compounds isomeric with the sulphocyanic ethers.—I. On the mustard oil of the ethyl series

1868 ◽  
Vol 16 ◽  
pp. 254-258
Keyword(s):  
Royal Society ◽  
The Other ◽  
Mustard Oil ◽  
Other Hand ◽  
Derivatives Of

The results of my researches on the chloroform-derivatives of the primary monamines, which, as I have shown, are isomeric with the nitriles, could not fail to direct my attention to allied groups of bodies, with the view of discovering similar isomerisms. In a note communicated to the Royal Society some months ago, I expressed the expectations which even then appeared to be justified in the following manner:—“In conclusion, I may be permitted to announce as everv probable the existence of a series of bodies isomeric with the sulphocyanides. Already M. Cloëz has shown that the action of chloride of cyanogen on ethylate of potassium gives rise to the formation of an ethylic cyanate possessing properties absolutely different from those belonging to the cyanate discovered by M. Wurtz. On comparing, on the other hand the properties of the methylic and ethylic sulphocyamdes with those of the sulphocyanides of allyl and phenyl, it can scarcely be doubted that we have here the representatives of two groups entirely different, and that the terms of the methyl- and ethyl-series which correspond to oil of mustard, and to the sulphocyanide of phenyl, still remain to be discovered. Experiments with which I am now engaged will show whether these bodies cannot be obtained by the action of the iodides of methyl and ethyl on sulphocyanide of silver."

Comparative Spectroscopic Studies on Luminescence Performance of Er3+ Doped Tellurite Glass Embedded with Different Nanoparticles (Ag Co and Fe) at 0.55 μm Emission

2021 ◽  
Vol 317 ◽  
pp. 81-86
Author(s):  
Syariffah Nurathirah Syed Yaacob ◽  
Md. Rahim Sahar ◽  
Faizani Mohd Noor ◽  
Nur Liyana Amiar Rodin ◽  
Siti Khadijah Mohd Zain ◽  
...  
Keyword(s):  
Energy Transfer ◽  
Ground State ◽  
Tellurite Glass ◽  
Spectroscopic Studies ◽  
The Other ◽  
X Ray Diffraction ◽  
Melt Quenching ◽  
X Ray ◽  
Doped Glass ◽  
Luminescence Performance

The spectroscopic performance of Er3+ doped glass at 0.55 mm emission contain different nanoparticles NPs have been comparatively evaluated. Glass containing 1.0 mol % of Er3+ doped with different NPs (Ag, Co and Fe ) have been prepared using melt quenching technique. X-ray diffraction analysis reveals the all the prepared samples are amorphous. The UV-Vis absorption spectra of all glasses show several prominent peaks at 525 nm, 660 nm, 801nm, 982 nm and 959 nm due to transition from ground state 4I15/2 to different excited of 2H11/2, 4F9/2, 4I9/2, 4I11/2, and 4I13/2. The emission of Er3+ at 0.55 mm for glass contain Ag NP shows significant enhancement about 3 folds up to 0.6 mol%. On the other hand, the emission of Er3+ at 0.55 mm for glass containing Fe NPs and Co NPs intensely quench probably due to the energy-transfer from Er3+ ion to NPs and magnetic contributions.

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