Diamagnetic susceptibilities

Correspondingly, the specific sensitivity parameters can be introduced diamagnetic susceptibility as the response under applied magnetic field, static dipole polarizability that accounts for the electronic cloud deformation under applied electric perturbation and the chemical hardness associated with the compactness of the electronic cloud by the nuclear influence, and possible applied electric perturbation. 

Therefore, these are the descriptors that are sensitive to the external applied fields so that can give through the suitable experiments the useful structure information. In the follow we quantify these structure indices in terms of atomic radii performing the correspondence between the full atomic quantities (total number of electrons, nuclear chaige and the spatial averages) and those related with atomic radii (the outer electrons, the effective charge of the outer shell and the atomic radii itself) (Putz et al., 2003, 2012b,c)  

Let s consider an electron with elementary charge e and mass m orbiting with the velocity v at the distance r of nucleus. Its movement produces a microscopic electrical current  

Quantum Nanochemistry—Volume II Quantum Atoms and Periodicity 

Being the orbital area A = nr that associates with the orbital current, the corresponding magnetic moment can be written as their product  

A knowledge of the solubilities of phosgene in liquids is important, not only from the point of view of recognizing suitable media in which to perform reactions, but also to enable the correct choice of solvent for the purposes of extraction. 

Owing to its poisonous nature, and for economic reasons, it is desirable to be able to remove phosgene from air. Scrubbing the phosgene-air mixture with liquid absorbent is a useful technique, and quantitative data are required in order to design suitable absorption equipment. 

The low solubility of phosgene in water renders this solvent as unsuitable, and organic liquids are usually employed in extractive processes. A common way to treat effluents contaminated with phosgene is to absorb the gas into a suitable solvent (commonly one that is used as the medium for the main reaction) it is then possible to regenerate the phosgene 

Coal-tar fraction. Residue of crude petroleum oil unspecified composition. Unspecified composition, but probably a high boiling fraction of coal tar. 

The industrial reaction of phosgene with primary amines produces large quantities of by-product hydrogen chloride (see Section 4.7.1) that is contaminated with phosgene. Although most of the COCl is removable by cooling, it may be desirable to purify the HCi 

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However, there are other molecular properties, such as molar volume, molar refi action [3], diamagnetic susceptibility [4], and parachor [5], that can be obtained to sufficient accuracy fi om contributions, p , of its N atoms (Eq. (5)). 

The molar diamagnetic susceptibility of thiazole and some derivatives was initially determined by the classical Curie-Cheneveau method (5,315,316) and later confirmed by a method (317) based on the difference of NMR proton chemical shift of a sample of tetramethylsilane immersed in the liquid to be investigated, according to the shape (cylindrical or spherical) of the sample tube (Table 1-47) (318),... 

The sydnones may be represented by structures (123a-d), of which the zwitterionic structure (123a) most clearly implies an aromatic sextet. The diamagnetic susceptibility exaltation for Af-phenylsydnone of ll.Ox 10 cm moP is comparable with the corresponding value for pyrrole (10.2x10 ). 3-p-Bromophenylsydnone (123 R = H, R = p-bromophenyl) is essentially planar however, the O—N bond and 0(1)—C(5) bond lengths are not very different from normal single bond distances. 

Furazano[3,4-/]quinoxaline, 7,8-diphenyl-synthesis, 6, 412 Furazanothiophene synthesis, 6, 417 Furazans, 6, 393-426 biological activity, 6, 425 bond angles, 6, 396 bond lengths, 6, 396 coordination compounds, 6, 403 diamagnetic susceptibilities, 6, 395 dipole moments, 6, 395, 400 heats of combustion, 6, 400 heterocyclic ring reactions, 6, 400-403 IR spectra, 6, 398 isoxazoles from, 6, 81 mass spectra, 6, 399 microwave spectroscopy, 6, 395, 396 MO calculations, 6, 395 monosubstituted... 

Diamagnetic susceptibility of a spherically symmetrical system, 68 -dibromobenzene p-C6H479Br), ethylene system, 102 quadrupole spectrum, 195 />-dibromophenyl p- (CflH4)279Br2), quadrupole spectrum, 195 radiation resistance of, 200... 

Other physical methods were also applied to the elucidation of the isomerism of diazocyanides, e. g., determination of diamagnetic susceptibility, the Faraday effect (optical rotation in a magnetic field), and electronic and infrared spectra. Hantzsch and Schulze measured ultraviolet spectra at a remarkably early date (1895 a). Unfortunately, their results and later work (Le Fevre and Wilson, 1949 Freeman and Le Fevre, 1950) did not allow unambiguous conclusions, except perhaps the observation that the molar extinction coefficients of the band at lowest frequency are consistently larger in all types of (i -compounds Ar — N2 - X than in the corresponding (Z)-iso-mers (Zollinger, 1961, p. 62). 

The /3- and -phases are not unlike their component metals in properties such as luster, malleability, and electrical resistivity. The 7-phase, however, shows striking differences it is brittle and is associated with sharp maxima in electrical resistivity7 and diamagnetic susceptibility.8... 

The Theoi etical Prediction of the Physical Properties of Many-Electron Atoms and Ions. Mole Refraction Diamagnetic Susceptibility, and. Extension in Space... 

Table IV.—The Mole Refraction and Diamagnetic Susceptibility of Atoms and Ions.

The molal diamagnetic susceptibilities of rare gas atoms and a number of monatomic ions obtained by the use of equation (34) are given in Table IV. The values for the hydrogen-like atoms and ions are accurate, since here the screening constant is zero. It was found necessary to take into consideration in all cases except the neon (and helium) structure not only the outermost electron shell but also the next inner shell, whose contribution is for argon 5 per cent., for krypton 12 per cent., and for xenon 20 per cent, of the total. 

We can draw conclusions regarding deformation of ions from observations of the diamagnetic susceptibility just as from those of the mole refraction. Thus in the series C03 , N03 and PO, SO4" the experimental values of / show successively greater deviations from the theoretical ones (assuming undeformed 0= ions) with increasing electrical charge of the central ion. ... 

We may accordingly conclude that our theoretical values of the diamagnetic susceptibility of atoms and ions are not incompatible with the experimental data. 

Added February 10, 1927.—J. H. Van Vleck in Proc. Nat. Acad. America, vol. 12, p. 662 (December, 1926), has discussed the mole refraction and the diamagnetic susceptibility of hydrogen-like atoms with the use of the wave mechanics, obtaining results identical with our equations (24) and (34). He also considered the effect of the relativity corrections (which is equivalent to the effect of a central field) and concluded that equation (24), derived by the use of parabolic instead of spherical co-ordinates, is not invalidated.]... 

Values of the diamagnetic anisotropy of benzene and other aromatic hydrocarbon molecules are calculated on the basis of the assumption that the p, electrons (one per aromatic carbon atom) are free to move from carbon atom to adjacent carbon atom under the influence of the impressed fields. When combined with the assumed values for the contributions of the other electrons (-2.0X 10-6 for hydrogen, —4.5 X10 c for aromatic carbon, — 6.0XlO-6 for aliphatic carbon) these lead to principal diamagnetic susceptibilities of molecules in approximate agreement with the available experimental data. The diamagnetic anisotropy of graphite is also discussed. 

A qualitative explanation of these abnormally large diamagnetic susceptibilities as arising from the Larmor precession of electrons in orbits including many nuclei3 has come to be generally accepted. With the aid of simple assumptions, I have now developed this idea into an approximate quantitative treatment, described below. 

The contribution of the electron to the diamagnetic susceptibility of the system can be calculated by the methods of quantum-mechanical perturbation theory, a second-order perturbation treatment being needed for the term in 3C and a first-order treatment for that in 3C". In case that the potential function in 3C° is cylindrical symmetrical about the s axis, the effect of 3C vanishes, and the contribution of the electron to the susceptibility (per mole) is given... 

Figure 9. Variation of the diamagnetic susceptibility as a function of boron doping.

Kimira, T, Yoshino, M., Yamane, T, Yamato, M. andTobita, M. (2004) Uniaxial alignment of the smallest diamagnetic susceptibility axis using time-dependent magnetic fields. Langmuir, 20, 5669-5672. 

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