Diamagnetic susceptibility elements

Dew point and relative humidity, 15-31 Diamagnetic susceptibility elements, 4-142 to 147 inorganic compounds, 4-142 to 147 organic compounds, 3-672 to 676 Diamagnetic Susceptibility of Selected... 

Table 2. The factors q mx1- n V f°r maSnetic induced corrections to the matrix elements of radiative 7r-transitions in the Lyman nOA-) —> Is) and Balmer series nOA- —> 12s) and nmA+) — 2pm) with m = 0,1. The upper level index A is determined by ordering the absolute values of diamagnetic susceptibility, reP ...

Finally, in the third section of this paper, we describe a semiempirical atom dipole model that allows a reliable prediction of molecular electric dipole and quadrupole moments, diamagnetic susceptibilities, and diamagnetic nuclear shieldings. A set of localized bond and atom values are developed for the individual diagonal elements in the total molecular magnetic susceptibility tensor. 

If the diamagnetic behavior of matter could be completely explained by local currents around the nuclei, and if the diamagnetic susceptibility of the different nuclei of the periodic table were known, the susceptibility of molecular compounds consisting of different elements would be the sum of the individual contributions, and could be easily predicted. As early as 1919, Pascal [23], and later Pacault [24] and Haberditzl [25], published simple increment systems to calculate diamagnetic susceptibilities of molecules. The increment system is quite accurate for most organic and inorganic compounds, with a few exceptions. 

TABLE 4.17 For the First Four Periods Of Elements, Using the DFT Atomic Radii (Second Colurrm), There Are Displayed the Calculated Diamagnetic Susceptibility, Static Dipole Polarizability, the Softness and Electronegativity Related Chemical Elardness and the Experimental First Ionization Potentials, From the Left to the Right Colunms, Respectively (Putz et ah, 2003, 2012b,c)... 

The effect will depend on the number and distribution of electrons, and is therefore roughly constant for a given element. The approximate molar diamagnetic susceptibility y can be calculated by taking the tabulated contributions from the known values for each element, called Pascal s constants (Table 1), and adding them up, e.g.,... 

Here, n, is the number of atoms of kind i, x fbeir susceptibility per gram-atom, and the sum extends over all atoms in the molecule. In addition, is the number of certain structural elements of kind j, Apj their contribution to the susceptibility, and the sum is over all these contributions. The quantities Xai and /Ipj are called the Pascal constants and the constitutive corrections, respectively. The most frequently used constants Za and constitutive corrections Ap are listed in Tab. 7. In general, the diamagnetic susceptibility of an organic substance may be estimated on the basis of the tabulated values with an accuracy of a few percent. Even though the Pascal scheme was established purely on an empirical basis, it is justified by more recent calculations involving molecular orbital theory [170]. Critical discussions and reviews on the subject are available in the literature [118, 167] and illuminating examples for the calculation of susceptibilities within the Pascal scheme are included in various textbooks [2,8,14]. 

According to P. Pascal,0 fluorine is diamagnetic the specific magnetic susceptibility is —3447 X10 j and the atomic susceptibilitv calculated from the additive law of mixtures for organic compounds is —63X10-1. Ionic fluorine is univalent and negative. The decomposition voltage required to separate this element from its compounds is 1 75 volts.7 The ionic velocity (transport number) 8 of fluorine ions at 18° is 46 6, and 52-5 at 25° with a temp, coeff. of 0 0238. 

The dielectric constant of solid white phosphorus was found to be 4-1 at 20° C., and that of liquid phosphorus 8-85 at 45°.3 The electrochemical potential is said to lie between those of arsenic and tellurium.4 Phosphorus is diamagnetic.8 The magnetic susceptibility of the solid white element is about 0-9 x 10 6 mass units, that of the red variety rather less.6... 

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