An application of group theory and the dipole moment correlation function to the dielectric relaxation in site models

1971 ◽  
Vol 67 ◽  
pp. 990 ◽  
Author(s):  
Graham Williams ◽  
Michael Cook
Keyword(s):  
Correlation Function ◽  
Dipole Moment ◽  
Group Theory ◽  
Dielectric Relaxation

Dielectric relaxation time and dipole moment of isometric butanols in benzene solutions.

1983 ◽  
Vol 26 (2) ◽  
pp. 77-84 ◽  
Author(s):  
S.M. Khameshara ◽  
M.S. Kavadia ◽  
M.S. Lodha ◽  
D.C. Mathur ◽  
V.K. Vaidya
Keyword(s):  
Dipole Moment ◽  
Relaxation Time ◽  
Dielectric Relaxation ◽  
Dielectric Relaxation Time

Dipole Moment and Dielectric Relaxation of Some Aromatic Ethylenes and Butadienes

1980 ◽  
Vol 35 (6) ◽  
pp. 623-627 ◽  
Author(s):  
F. F. Hanna ◽  
K. N. Abdel-Nour ◽  
J. E. Risk
Keyword(s):  
Dipole Moment ◽  
Dielectric Relaxation ◽  
Steric Hindrance ◽  
Relaxation Times

The dipole moment of 1,1-bis-p-chlorophenylethylene, 1,1-bis-p-bromophenylethylene, 1,1-bis-pmethoxy, -ethoxy, -isopropoxy-phenyl-ethylene, 1,1,4,4-tetrakis-p-methoxy, -ethoxy, isopropoxyphenylbuta- l,3dienes was measured and compared with the calculated value. The mesomeric moment was estimated and found to decrease in the case of the ethylenes with the increase in volume of the substituted group. For the butadienes, the mesomeric moments compensate each other.Investigations of the dielectric relaxation times of the ethylenes showed that the orientation of the -OCH3 group in the 1,1-bis-p-methoxy-phenylethylene is hindered to a large extent. The orientation of the -OC2H5 and -OC3H7 groups in the corresponding molecules are restricted due to steric hindrance

The Application of the Memory-Function Formalism to Dielectric Relaxation

1980 ◽  
Vol 35 (11) ◽  
pp. 1207-1217
Author(s):  
P. Bordewijk
Keyword(s):  
Correlation Function ◽  
Dielectric Relaxation ◽  
Single Molecule ◽  
Rotational Diffusion ◽  
Memory Function ◽  
Dielectric Relaxation Time ◽  
Function Formalism ◽  
Correlation Theorem ◽  
Dipole Correlation ◽  
Rotational Diffusion Coefficient

Abstract The application of the memory-function formalism to dielectric relaxation is reconsidered. It is shown that the so-called Corresponding Micro-Macro Correlation theorem is not valid and that for a single macroscopic dielectric relaxation time, the single-molecule dipole correlation function may nevertheless be non-exponential. The deviations from the exponential decay for the single-molecule dipole correlation function are due to spatially dependent orientational correlations, and can at least partly be interpreted in terms of dielectric friction. The unsureness about these correlations implies that it is simpler to determine the rotational diffusion coefficient from the collective orientation correlation time as determined from dielectric measurements than from the single-molecule dipole correlation function as obtained from infrared spectroscopy.

Considerations for the Construction of the Solvation Correlation Function and Implications for the Interpretation of Dielectric Relaxation in Proteins

2009 ◽  
Vol 113 (32) ◽  
pp. 11061-11068 ◽  
Author(s):  
Sayantan Bose ◽  
Ramkrishna Adhikary ◽  
Prasun Mukherjee ◽  
Xueyu Song ◽  
Jacob W. Petrich
Keyword(s):  
Correlation Function ◽  
Dielectric Relaxation

Dielectric Relaxation Studies of Ternary Mixture of Dimethyl Phthalate and Heptanol in Benzene Solution in the Microwave Region

2015 ◽  
Vol 70 (7) ◽  
pp. 507-512
Author(s):  
A. Mushtaq Ahmed Khan ◽  
M. Subramanian
Keyword(s):  
Dielectric Constant ◽  
Dipole Moment ◽  
Relaxation Time ◽  
Dielectric Relaxation ◽  
Benzene Solution ◽  
Microwave Frequency ◽  
Viscous Force ◽  
Dimethyl Phthalate ◽  
Flow Process ◽  
Relaxation Studies

AbstractThe molecular structure and molecular forces in liquids and solutions, in particular, have been investigated by dielectric relaxation studies. The nature and strength of the molecular interactions have been established as the main cause for the chemical behaviour of compounds. The dielectric behaviour of dimethyl phthalate with heptanol in benzene solution has been studied at a microwave frequency of 9.36 GHz at different temperatures 303, 308, and 313 K. Different dielectric quantities such as dielectric constant (ε′), dielectric loss (ε″), static dielectric constant (ε0), and dielectric constant at optical frequency (ε∞) have been determined. The relaxation time τ has been calculated by both Higasi’s method and Cole–Cole method. The dielectric relaxation process can be treated as a rate process just like the viscous flow process. The complex system investigated shows the maximum relaxation time values at high temperatures by both Higasi’s method and Cole–Cole method. The molar free energies of activation of dipole moment (ΔFτ) and viscous force (ΔFη) have also been reported. The excess dipole moment is also determined. The excess dipole moment is a qualitative index for the presence of a hydrogen bond in the ternary system. The value of Δμ obtained in our study indicates the presence of hydrogen bonds between the components of the mixture. The system investigated shows that the relaxation time value increases with the increase in the concentration of solute.

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