[01] D. P. Nandedkar, Department of Electrical Engineering, Indian Institute of Technology, Bombay, Powai, Mumbai, India.

The study of dipole relaxation time for water molecules at 293⁰K is an important aspect from physics / communication / electronic engineering point of view since it gives rise to the dielectric absorption losses for r.f. fields up to about 3 x10¹⁰ Hz of frequencies. Here molecular (dipole) relaxation time is analyzed and calculated for the water molecules at temperature of 293⁰K. This assumes that the water medium is an intermediate one to a solid state and a gaseous state. The molecule of the water undergoes coupled mass vibrations on one hand and simultaneously it has an average thermal velocity on other hand as given by the kinetic theory of gasses. In other words, this is a quasi-stationary: quasi moving system of the molecules, where molecule-molecule collisions take place which are described by gas kinetics. The expression which is obtained for the molecular collision frequency, determines the dipole relaxation time coming in the picture of relaxation spectrum in r.f. region for the water molecules. The present theory given here determines fairly well the value of dipole relaxation time for water at temperature of 293⁰K, viz., the relaxation time is experimentally located near the free space wavelength of 1 cm in the relaxation spectrum of water. Purpose of this work is to show in a simple manner, how dipole relaxation time for water molecules at 293⁰K comes in the analysis of scattering of the dipoles at collisions with each other.

Water, Coupled-Mass-Vibrations, Molecule-Molecule, Collisions, Dipole-Relaxation, 293⁰K

[01] Von HIppel, A. R., (1954): “Dielectric Materials and Applications”, Technology Press of MIT and John Wiley and Sons, New York, Chapman and Hall Ltd, London [02] Dekker, A.J., (1961): “Electrical Engineering Materials”, Second Printing, Prentice Hall, Inc, Englewood Cliffe, N. J. [03] Stark J., (1914): Ann. Physik, 43, 965, 983, 991 [04] Debye P., (1945): “Polar Molecules”, pp. 77-89 Dover Publications, New York [05] Fro ̈hlich H., (1949): “Theory of Dielectrics”, pp.73, Clarendon Press, Oxford [06] Cole K. S. and Cole R. H., (1941): “J. Chem. Phys.”, 9, 341 [07] Buchner R, Barthel J. and Stauber J., (1999): “The dielectric relaxation of water between 0°C and 35°C”, Chemical Physics Letters, Vol. 306, Issues 1-2, 4, pages 57-63, June 1999 [08] Thakur, O. P. and Singh A. K., (2008): “Anaylysis of dielectric relaxation in water at microwave frequency”, Adv. Studies Theor. Phys., Vol. 2, No. 13, 637-644 [09] Zasetsky A. Y., (2011): “Dieletric relaxation in liquid: Two fractions or two dynamics?”, Physical Rev. Letters, 107, 117601 Sept. 2011 [10] Clark, J.B., (1988): “Clark’s Tables (science Data Book), Orient Longman Limited, Hyderabad, Indian Reprinted Edition [11] Nandedkar, D.P., (2015): “Analysis of Conductivity of Noble Metals near Room Temperature”, Voi. 1, No. 3, pp. 255, Phys. Journal (PSF), AIS [12] Nandedkar, D. P., (2015): “Analysis of Mobility of Intrinsic Germanium and Silicon near Room Temperature” –Accepted for Publication, to aiscience.org on 18-Oct-2015 (Physics Journal: Paper No 70310075), PSF, AIS [13] Kittel, C., (1960): “Introduction to Solid State Physics”, First/Second Indian Edition, Asia Publishing House, Bombay (Original US second edition, 1956, Published by John Wiley and Sons, Inc New York)