Dipole moment and molecular structure. Part XVII. The dipole moments of azo-dyes and some similar substances

1936 ◽  
Vol 32 ◽  
pp. 1318 ◽  
Author(s):  
Ernst Bergmann ◽  
Anna Weizmann
Keyword(s):  
Molecular Structure ◽  
Dipole Moment ◽  
Azo Dyes ◽  
Dipole Moments

scholarly journals Dipole moments and molecular structure. Part I.— A simple resonance method for the measurement of dielectric constants

1932 ◽  
Vol 136 (829) ◽  
pp. 251-255 ◽  
Keyword(s):  
Molecular Structure ◽  
Dipole Moment ◽  
Dipole Moments ◽  
Resonance Method ◽  
Dielectric Constants ◽  
Present Communication ◽  
Dilute Solutions ◽  
Resonance Circuit ◽  
Low Resistance ◽  
Voltage Resonance

Numerous types of resonance methods for the measurement of dielectric constants have been described by different investigators. That detailed in the present communication has no claim to originality, but it is a simple, whilst at the same time reliable, form, which has proved to be very useful for the measurement of the dielectric constants of dilute solutions for the purpose of dipole moment determination. A fairly powerful oscillator is used, enabling the valveless resonance circuit to be some distance removed from it, whilst still receiving ample “pick-up” for the measurements. Resonance in the pick-up circuit is detected by means of a low-resistance thermo-junction, introduced directly into the circuit. The resistance thus introduced does not damp the oscillation unduly. The very small conductivity of the solvent liquids employed does not produce any appreciable error owing to the current resonance not occurring at the same tuning capacity as the voltage resonance.

Determination of dipole moment values of anisotropic molecules using Brot's formalism

1990 ◽  
Vol 68 (9) ◽  
pp. 1523-1526
Author(s):  
P. Brito ◽  
M. Mechetti
Keyword(s):  
Molecular Structure ◽  
Dipole Moment ◽  
Dipole Moments ◽  
Dilute Solutions ◽  
Molecular Anisotropy ◽  
Derivatives Of ◽  
Best Parameters

A method for the determination of dipole moment values based on Brot's theory is proposed. It takes into account the influence of the molecular anisotropies of shape and polarizability on the permittivity of a mixture. Starting from measurements performed on dilute solutions and from the knowledge of the molecular structure of some chlorinated derivatives of α-cyanostilbene and 1,3 derivatives of benzene, the best parameters of an ellipsoid used for the representation of a polar anisotropic molecule are determined. The dipole moments obtained, using benzene and tetrachloromethane as solvents, are finally compared to values from the literature. Keywords: dipole moment, Brot's formalism, molecular anisotropy.

Three-membered Rings. Molecular Structure and Conformation of Aryl Substituted Oxiranes by Dipole Moment Measurements

1977 ◽  
Vol 32 (12) ◽  
pp. 1467-1472 ◽  
Author(s):  
Salvatore Sorriso ◽  
Carlo Battistini ◽  
Bruno Macchia ◽  
Franco Macchia
Keyword(s):  
Molecular Structure ◽  
Dipole Moment ◽  
Electric Dipole ◽  
Dipole Moments ◽  
Phenyl Group ◽  
Electric Dipole Moments ◽  
Bond Angles ◽  
Styrene Derivatives

The electric dipole moments of some styrene and trans- and cis-stilbene oxides have been measured, in benzene. From these data some bond angles have been calculated and it has been deduced that in the styrene derivatives the phenyl group is in rapid interconversion about the bond with the triatomic ring.

Molecular structure of para-substituted 3-aryl-2-arylmethylene-3-oxopropanenitriles in solution phase

1985 ◽  
Vol 50 (9) ◽  
pp. 1935-1947 ◽  
Author(s):  
Štefan Marchalín ◽  
Václav Jehlička ◽  
Stanislav Böhm ◽  
Petr Trška ◽  
Josef Kuthan
Keyword(s):  
Molecular Structure ◽  
Dipole Moment ◽  
Knoevenagel Condensation ◽  
Dipole Moments ◽  
Solution Phase ◽  
Conformational Structure ◽  
Spectral Measurements ◽  
Electrical Dipole ◽  
Dipolar Structure ◽  
C Nmr

The conformational structure of the title compounds has been investigated by application of EHT calculations, 1H and 13C NMR spectral measurements, and calculated/found electrical dipole moments. It has been proved that compounds Ia-Ie and IIa-IIf obtained by thermodynamically-controlled Knoevenagel condensation are all E isomers. The dipole moment of compound Ia indicates a partially dipolar structure.

Energies and Electric Dipole Moments of the Bound Vibrational States of HN2+ and DN2+

2008 ◽  
Vol 73 (6-7) ◽  
pp. 873-897 ◽  
Author(s):  
Vladimír Špirko ◽  
Ota Bludský ◽  
Wolfgang P. Kraemer
Keyword(s):  
Dipole Moment ◽  
Nearest Neighbor ◽  
Energy Surface ◽  
Dipole Moments ◽  
Three Dimensional ◽  
Vibrational States ◽  
Spacing Distribution ◽  
Triatomic Molecules ◽  
Vibrational Levels ◽  
Different Levels

The adiabatic three-dimensional potential energy surface and the corresponding dipole moment surface describing the ground electronic state of HN2+ (Χ1Σ+) are calculated at different levels of ab initio theory. The calculations cover the entire bound part of the potential up to its lowest dissociation channel including the isomerization barrier. Energies of all bound vibrational and low-lying ro-vibrational levels are determined in a fully variational procedure using the Suttcliffe-Tennyson Hamiltonian for triatomic molecules. They are in close agreement with the available experimental numbers. From the dipole moment function effective dipoles and transition moments are obtained for all the calculated vibrational and ro-vibrational states. Statistical tools such as the density of states or the nearest-neighbor level spacing distribution (NNSD) are applied to describe and analyse general patterns and characteristics of the energy and dipole results calculated for the massively large number of states of the strongly bound HN2+ ion and its deuterated isotopomer.

scholarly journals DERIVATION OF GENERALIZED THOMAS–BARGMANN–MICHEL–TELEGDI EQUATION FOR A PARTICLE WITH ELECTRIC DIPOLE MOMENT

2013 ◽  
Vol 28 (29) ◽  
pp. 1350147 ◽  
Author(s):  
TAKESHI FUKUYAMA ◽  
ALEXANDER J. SILENKO
Keyword(s):  
Dipole Moment ◽  
Electromagnetic Fields ◽  
Electric Dipole Moment ◽  
Electric Dipole ◽  
Dipole Moments ◽  
Classical Equation ◽  
Spin Motion ◽  
Electric Dipole Moments ◽  
Momentum Direction ◽  
Telegdi Equation

General classical equation of spin motion is explicitly derived for a particle with magnetic and electric dipole moments in electromagnetic fields. Equation describing the spin motion relative to the momentum direction in storage rings is also obtained.

Charge-Transfer Dipoles at the Si-SiO2 Interface and the Metal-Semiconductor Worfunction Difference In Mos Devices.

1987 ◽  
Vol 105 ◽  
Author(s):  
Hisham Z. Massoud
Keyword(s):  
Dipole Moment ◽  
Charge Transfer ◽  
Dipole Moments ◽  
Silicon Substrates ◽  
Interface Dipole ◽  
Mos Devices ◽  
Flatband Voltage ◽  
The Difference ◽  
Definition Of ◽  
Mos Structures

AbstractThe magnitude of the dipole moment at the Si-SiO2 interface resulting from partial charge transfer that takes place upon the formation of interface bonds has been calculated. The charge transfer occurs because of the difference in electronegativity between silicon atoms and SiO2 molecules which are present across the interface. Results obtained for (100) and (111) silicon substrates indicate that the magnitude of the interface dipole moment is dependent on substrate orientation and the interface chemistry. Dipole moments at the Si-SiO2 and gate-SiO2 interfaces should be included in the definition of the flatband voltage VFB of MOS structures. CV-based measurements of the metal-semiconductor workfunction difference φms on (100) and (111) silicon oxidized in dry oxygen and metallized with Al agree with the predictions of this model. Other types of interface dipoles and their processing dependence are briefly discussed.

Experimental and computed dipole moments in donor–bridge–acceptor systems with p-phenylene and p-carboranediyl bridges

2009 ◽  
Vol 74 (1) ◽  
pp. 131-146 ◽  
Author(s):  
Ladislav Drož ◽  
Mark A. Fox ◽  
Drahomír Hnyk ◽  
Paul J. Low ◽  
J. A. Hugh MacBride ◽  
...  
Keyword(s):  
Dipole Moment ◽  
Dipole Moments ◽  
Electronic Effects ◽  
Electronic Interactions ◽  
Donor And Acceptor ◽  
Homo And Lumo ◽  
Pull Systems ◽  
The Difference ◽  
Experimental Values ◽  
2D And 3D

Dipole moments were measured for a series of substituted benzenes, biphenyls, terphenyls, C-monoaryl- and C,C′-diaryl-p-carboranes. For the donor–bridge–acceptor systems, Me2N–X–NO2, where X is 1,4-phenylene, biphenyl-4,4′-diyl, terphenyl and 1,4-C6H4-p-CB10H10C-1,4-C6H4, the measured interaction dipole moments are 1.36, 0.74, 0.51 and 0.00 D, respectively. The magnitude of the dipole moment reflects the ability of the bridge to transmit electronic effects between donor and acceptor groups. Thus, whilst the 1,4-phenylene bridges allow moderate electronic interactions between the remote groups, the p-carboranediyl unit is less efficient as a conduit for electronic effects. Averaged dipole moments computed at the DFT (B3LYP/6-31G*) level of theory from two distinct molecular conformers are in good agreement with the experimental values. Examination of the calculated electronic structures provides insight into the nature of the interactions between the donor and acceptor moieties through these 2D and 3D aromatic bridges. The most significant cooperative effect of the bridge on the dipole moment occurs in systems where there is some overlap between the HOMO and LUMO orbitals. This orbital overlap criterion may help to define the difference between “push-pull” systems in which electronic effects are mediated by the bridging moiety, and simpler systems in which the bridge acts as an electronically innocent spacer unit and through-space charge transfer/separation is dominant.

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