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Magnetic data

Table 7.3. Shock-modified powders Crystallite size, strain, and static magnetization data on hematite (after Williamson et al. [86W03]). Table 7.3. Shock-modified powders Crystallite size, strain, and static magnetization data on hematite (after Williamson et al. [86W03]).
This by no means exhaustive discussion may serve to indicate the value of the information provided by magnetic data relative to the nature of the chemical bond. The quantum-mechanical rules for electron-pair bonds are essential to the treatment. Much further information is provided when these methods of attack are combined with crystal structure data, a topic which has been almost completely neglected in this paper. It has been found that the rules for electron-pair bonds permit the formulation of a set of structural principles for non-ionic inorganic crystals similar to that for complex ionic crystals the statement of these principles and applications illustrating their use will be the subject of an article to be published in the Zeitschrift fur Kristallographie. [Pg.97]

It is then shown that (excepting the rare-earth ions) the magnetic moment of a non-linear molecule or complex ion is determined by the number of unpaired electrons, being equal to ms = 2 /S(S + 1), in which 5 is half that number. This makes it possible to determine from magnetic data which eigenfunctions are involved in bond formation, and so to decide between electron-pair bonds and ionic or ion-dipole bonds for various complexes. It is found that the transition-group elements almost without exception form electron-pair bonds with CN, ionic bonds with F, and ion-dipole bonds with H2O with other groups the bond type varies. [Pg.98]

Examples of deductions regarding atomic arrangement, bond angles and other properties of molecules and complex ions from magnetic data, with the aid of calculations involving bond eigenfunctions, are given. [Pg.98]

It is indicated by the observed interatomic distances and shown by magnetic data that there occurs some deviation from this simple and attractive scheme in the middle region of the sequence. From chromium to cobalt the interatomic distances do not continue to decrease in value, as expected with increase in the number of bonds instead they remain nearly constant Cr, A2, 2.49A Mn, no simple structure Fe, A2, 2.48A, Al, 2.52A Co, Al, A3, 2.50-2.51A Ni,... [Pg.346]

The numbers 5.78 and 2.44 were obtained in 1938 by the analysis of these magnetic data. It is seen from Fig. 1 that the experimental points are not precisely represented by straight lines with slope +1 and —1, and that, accordingly, there is some uncertainty in the construction of these lines and, hence, in the number of bonding orbitals and the number of stable atomic orbitals deduced from them. The full lines in Fig. 1 are those selected in 1938. The dashed lines, which... [Pg.365]

J Possibly slightly different valencies should be assumed, especially for ruthenium and osmium, and a small change may be required when reliable magnetic data become available. [Pg.387]

A sterically hindered homoleptic samarium(lll) tris(amidinate), Sm[HC (NC6H3Pr2-2,6)2]3, was obtained by oxidation of the corresponding Sm(II) precursor (cf. Scheme 54). Magnetic data and the results of low temperature absorption, luminescence, and magnetic circular dichrosim spectra have been... [Pg.237]

Compound Preparation Crystallo- graphic data Optical properties Magnetic data Other physical data... [Pg.365]

IR and Raman spectra of the NbS2X2 compounds have been measured, and assigned to the different modes (271). Especially in the absence of X-ray data, such measurements serve to prove the presence of S-S and Nb-S modes (see Table X). Magnetic data are available for... [Pg.367]

MCD results more or less confirmed the conclusions drawn from previous EPR data (27). The shapes of the MCD spectra of the putative prismane protein in the 3+, 4+, and 5+ states had not been observed for any Fe-S protein. This was not surprising, since every single type of Fe-S cluster is considered to exhibit a unique MCD spectrum. Magnetization data confirmed the S = ground state of the 5-1- state, as well as the S = 4 ground state of the 4+ state. Unexpectedly, in addition to the S = 4 contribution, a considerable diamagnetic contribution was observed for the 4-1- state. The nature of the diamagnetic contribution was not understood a physical spin mixture was considered to be a possible explanation. [Pg.230]

During the course of an attempted recrystallization of this complex from benzene containing chlorinated impurities the solution was exposed to light. The crystalline compound that formed from this solution was identified by X-ray crystallography as Mo(TPP)(Ph)Cl (Fig. 3). The complex contains Irons phenyl and chloro ligands, and the Mo—C and Mo—N4 plane distances are 2.241(1) and 0.125 A, respectively. A systematic synthesis of the complex could not subsequently be developed and consequently other spectroscopic and magnetic data were not collected. [Pg.243]

Few Ni4 complexes with a cubane-like structure and four triply bridging //3-l,l,l-N3 ligands symmetrically bound to three Ni11 ions have been discovered (886),2135,2156 but magnetic data are only reported in the case of [Ni4(dmb)4(EtOH)4(//3-l,l,l-N3)4] (dbm = dibenzoylmethane).2135,2136 Its magnetic behavior was well reproduced by a model with a single 7 = +11.9cm 1. [Pg.467]

The anionic substructure of the salt Cs2[Ni(N3)4] H202183 consists of a 2D structure formed by Ni(N3)6 octahedra connected via four EE azido groups placed in a distorted plane, but no magnetic data have been reported. [Pg.474]

The hemerythrin of Golfingia gouldii consists of eight subunits, each of which contains two iron atoms, in a protein with molecular weight 108,000. Spectral and magnetic data point to an oxo-bridged structure around the non-heme iron atom (99). Protein B2 of ribotide reductase of E. coli has some properties in common with hemerythrin presumably a protein corresponding to that of E. coli reduces ribotides in animal tissues, a conclusion based on probes with inhibitors. [Pg.166]


See other pages where Magnetic data is mentioned: [Pg.1698]    [Pg.189]    [Pg.246]    [Pg.66]    [Pg.170]    [Pg.170]    [Pg.64]    [Pg.88]    [Pg.94]    [Pg.76]    [Pg.15]    [Pg.42]    [Pg.45]    [Pg.46]    [Pg.47]    [Pg.50]    [Pg.178]    [Pg.333]    [Pg.87]    [Pg.411]    [Pg.425]    [Pg.69]    [Pg.254]    [Pg.448]    [Pg.463]    [Pg.464]    [Pg.467]    [Pg.467]    [Pg.472]    [Pg.474]    [Pg.474]    [Pg.475]    [Pg.477]    [Pg.478]    [Pg.479]    [Pg.210]   
See also in sourсe #XX -- [ Pg.477 ]

See also in sourсe #XX -- [ Pg.249 ]




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