Electronic moment

Dipole moments and total energies for pyrazolo[l,5-h]-s-triazole tautomeric forms 97a-97c were calculated using CNDO/2 and CNDO/S (76T341) the results predict the stability of tautomers in a 97a > 97b > 97c sequence. So far, no ab initio calculations or synthesis of 97 have been reported. For pyrazolo[3,2-c]-s-triazole 98 (76T341), the calculated dipole moments, electronic absorption, and proton chemical shifts are in a good... 

Note that majority electrons that are accelerated by the electric field in one of the cobalt layers contribute to the current, not only in that layer (I = J) but in other layers as well, including the copper layers and the cobalt layers on the other side of the copper. On the other hand, minority electrons that are accelerated by a field in one of the cobalt layers contribute very little to the conductivity in the copper or in the cobalt on the other side of the copper. For anti-parallel alignment of the moments, electrons that are accelerated by the field in one cobalt layer contribute to the current in that layer and in the cobalt, but not in the other cobalt layer. The difference in the lolal current due to both channels between parallel and anti-parallel alignment is almost entirely non-local. It comes from those electrons that are accelerated by the applied electric field in one cobalt layer and propagate across the copper to the other cobalt layer where they contribute to the current. It is clear from Figures 1-4 that this process occurs primarily for majority electrons and for the case of parallel alignment. 

There have been no reports of complexes of " JV-substituted thiosemicarbazones derived from 2-formylpyridine, but 2-acetylpyridine JV-methyl-thiosemicarbazone, 3a, formed [Fe(3a-H)2]C104 and [Fe(3a-H)2]FeCl4 [117]. The nature of these two species was established by partial elemental analyses, molar conductivities, magnetic moments, electronic, infrared, mass and electron spin resonance spectra. A crystal structure of a related selenosemicarbazone complex confirmed the presence of a distorted octahedral iron(III) cation coordinated by two deprotonated anions so that each ligand is essentially planar and the azomethine nitrogens are trans to each other the pyridyl nitrogen and selenium donors are both cis. 

Values of 0 measured by means of X-ray diffraction, dipole moment, electron diffraction, ultraviolet spectroscopy, and nmr spectroscopy for various sets of XpjtGXnp with G = ortho phenylene or cis-vinylene were successfully correlated with Eq. 58, supporting the validity of the model. 

Compton wavelength of neutron Compton wavelength of proton Diamagnetic shielding factor, spherical H20 molecule Electron g factor Electron magnetic moment Electron radius (classical) Electron rest mass... 

Examination of 3-indolyl compounds for relationships between antioxidation potential (using in vitro LP assays) and electronic, polar, and steric parameters, including bond dissociation energies, bond lengths, dipole moments, electronic charge densities, and molecular size parameters showed that antioxidant efficacy of 3-indolyl compounds was most strongly predicted... 

London dispersion force induced dipole-induced dipole The above two examples required a permanent charge to induce a dipole in a nonpolar molecule. A nonpolar molecule may also induce a temporary dipole on its identical neighbor in a pure substance. These forces occur because at any given moment, electrons are located within a certain region of the molecule, and the instantaneous location of electrons will induce a temporary dipole on neighboring molecules. For example, an isolated helium atom consists of a nucleus with a 2+ charge and two electrons in a spherical electron density cloud. An attraction of He atoms due to London dispersion forces (shown at right by the dashed line) occurs because when the electrons... 

Tajiri and Winkler have conducted quantum mechanical calculations on some thiadiazolo-thiadiazoles (6)-(9) within the framework of the Parriser-Paw-Pople (PPP) method and have successfully employed their theoretical results to assist in the interpretation and prediction of the magnetic circular dichroism (MCD) spectra of these molecules <83ZN(A)1263>. Despite the fact that sulfur 3d orbital participation is more or less unimportant in the prediction of dipole moments, electronic absorption spectra, or photoelectron spectra, the authors suggest that its significance for the evaluation of magnetic moments of sulfur-containing heterocycles merits further consideration. 

Electron spin magnetic moment)-(electron spin magnetic moment) dipolar interaction energy ... 

Ia) is included in the electronic Hamiltonian since, as we shall see, its most important effects arise from interactions involving electronic motions. The interactions which arise from electron spin, 30(5 ), will be derived later from relativistic quantum mechanics for the moment electron spin is introduced in a purely phenomenological manner. The electron-electron and electron-nuclear potential energies are included in equation (2.36) and the purely nuclear electrostatic repulsion is in equation (2.37). The double prime superscripts have been dropped for the sake of simplicity. We remind ourselves that // in equation (2.37) is the reduced nuclear mass, M M2/(M + M2). 

Keywords Dipole Moment, Electron transmission, Monolayer, Spin... 

We have recently completed a detailed study (27) of the dipole moment, electron affinity, and polarizability of LIF and the Isoelectronic BeO molecule. A wide range of basis sets were investigated to assure convergence of each of the properties and to serve as a guide for basis set selection for the heavier alkali halides. The results at the equilibrium geometries of LIF and BeO are compared in Table 1 together with those for HF, for which experimental polarizabilities are known. The columns... 

In most molecules, it is possible to describe the a—n interaction by simple electrostatic considerations and to explain in this way physical properties depending on them like dipole moments. Electron correlation seems to play no role, except for molecules with a very small polarity, like carbon monoxide 119>. The matter is more complicated for excitation phenomena, because it is necessary to take into account possible changes in the charge distribution, even if the electronic structure... 

There is no strict selection rule for vibration in the case of electronic transitions (i.e. between two different electronic states). The Condon principle states that the f .-variation of the (< / fL transition moment electronic matrix elements can in general be neglected... 

Further, we have considered the equilibrium configuration or distribution of the electrons within the molecule (dipole moments, electron density maps, and, for simple molecules, the spectroscopic description of the ground electronic states of molecules). We now have left a consideration of the displaceability of these electrons from their equilibrium configurations in their ground states. We have already encountered a term which is in effect a measure of this displaceability, namely the polarizability (see section 18). Since the molecule as a whole and especially its electrons must be subject to the quantum restrictions, the electrons cannot be considered as continuously displaceable but rather as capable of existing only in a... 

It became of interest to study the chemical properties of these compounds to gain some insights into how they may interact with the H2 histamine receptor. The analysis was simplified by concentrating on a series of antagonists depicted in Fig. 1 whose structures were closely related to cimetidine. The stodies emphasized the importance of such physicochemical properties as geometry, acidity (pX ), hydrophilicity (octanol-water partition, P) and dipole moment (electron density distribution). 

Normal or generalized coordinate Predictive correlation coefficient Quadrupole moment Electron density Bond order... 

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