TITLE

Experimental study of the high frequency relaxation process in monohydroxy alcohols

AUTHOR(S)
Murthy, S. S. N.; Tyagi, Madhusudan
PUB. DATE
August 2002
SOURCE
Journal of Chemical Physics;8/22/2002, Vol. 117 Issue 8, p3837
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
We have critically examined the possibility of the existence of yet another process (often referred to as process II in the literature) of much smaller magnitude on the high frequency side in the case of 2-ethyl-1-hexanol and 4-methyl-3-heptanol using the dielectric relaxation technique. We have also studied the mixtures of 2-ethyl-1-hexanol with nonpolar methylcyclohexane and a mixture of 1-bromobutane in 4-methyl-3-heptanol for this purpose. In addition, the differential scanning calorimetry (DSC) has been used to study the structural relaxation in the vicinity of the glass transition temperature using the Tool-Narayanaswami-Moynihan procedure as discussed by Sartor et al. [J. Phys. Chem. 100, 6801 (1996)]. Our results show the presence of a clear process II on the higher frequency side whose freezing-out corresponds to the glass transition event at T[sub g] in the DSC studies. It is suggested that process II is associated with free alcohol molecules and is connected to the structural relaxation in alcohols. The dielectric data have been analyzed to understand the thermodynamics of hydrogen bonding using the model of Dannhauser [J. Chem. Phys. 48, 1911 (1968)]. An attempt has been made to correlate the ratio of relaxation rates of processes I and II and the observed deviation from Debye behavior in the case of alcohols.
ACCESSION #
7131750

 

Related Articles

  • Dielectric relaxation of lower alcohols in the whole fluid phase. Hiejima, Yusuke; Yao, Makoto // Journal of Chemical Physics;10/15/2003, Vol. 119 Issue 15, p7931 

    Dielectric relaxation of ethanol and 1-propanol have been measured in a wide fluid phase including the supercritical condition for the first time. The results of the static permittivity [variant_greek_epsilon](0) and the dielectric relaxation time Ï„[sub D] are presented in the temperature...

  • Dynamics of glass-forming liquids. V. On the link between molecular dynamics and.... Richert, R.; Angeli, C.A. // Journal of Chemical Physics;6/1/1998, Vol. 108 Issue 21, p9016 

    Examines the dielectric formations of low molecular weight glass-forming liquids. Comparison between dielectric formations and configurational entropy; Dependence of temperature on liquid fragility and presence of Beta relaxation; Discussion of the Vogel-Fulcher theory fitting in terms of the...

  • Molecular dynamics simulations on the hydration of fluoroalcohols. Kinugawa, Kenichi; Nakanishi, Koichiro // Journal of Chemical Physics;11/1/1988, Vol. 89 Issue 9, p5834 

    Molecular dynamics (MD) calculations have been carried out for aqueous solutions of isopropyl alcohol (IPA) and its fluorinated compounds, 1,1,1-trifluoro-2-propanol (TFIPA) and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIPA). The simulated systems were canonical ensembles containing 216 molecules in...

  • Effects of induced steric hindrance on the dielectric behavior and H bonding in the supercooled liquid and vitreous alcohol. Johari, G. P.; Kalinovskaya, O. E.; Vij, J. K. // Journal of Chemical Physics;3/8/2001, Vol. 114 Issue 10 

    The extent of H bonding in alcohols may be reduced by sterically hindering its OH group. This technique is used here for investigating the reasons for the prominent Debye-type dielectric relaxation observed in monohydroxy alcohols [Kudlik et al., Europhys. Lett. 40, 549 (1997); Hansen et al., J....

  • Dielectric Relaxation Phenomena in Hydrogen-Bonded Liquids. Yomogida, Yoshiki; Nozaki, Ryusuke // AIP Conference Proceedings;2/21/2008, Vol. 982 Issue 1, p350 

    The complex permittivities of some monohydric alcohols and dihydric alcohols have been measured in the frequency range from 500 MHz to 20 GHz at temperatures between 273 K and 313 K. Analysis of dipole-dipole correlation factors indicates that cluster structures formed through intermolecular...

  • A molecular-dynamics simulation study of dielectric relaxation in a 1,4-polybutadiene melt. Smith, Grant D.; Borodin, Oleg; Paul, Wolfgang // Journal of Chemical Physics;12/8/2002, Vol. 117 Issue 22, p10350 

    We have carried out atomistic molecular dynamics simulations of a melt of 1,4-poly(butadiene) from temperatures well above the experimentally observed merging of the primary α process and secondary β process down to temperatures approaching the experimentally observed bifurcation...

  • Molecular dynamics in grafted layers of poly(dimethylsiloxane). Hartmann, L.; Kremer, F.; Pouret, P.; Léger, L. // Journal of Chemical Physics;4/1/2003, Vol. 118 Issue 13, p6052 

    Dielectric relaxation spectroscopy (10[sup -1]Hz to 10[sup 6] Hz) is employed to study the molecular dynamics of poly(dimethylsiloxane) (PDMS, M[sub w] = 1.7 × 10[sup 5] g mol[sup -1] and M[sub w] = 9.6 × 10[sup 4] g mol[sup -1]) as grafted films with thicknesses d below and above the...

  • Methanol-water solutions: A bi-percolating liquid mixture. Dougan, L.; Bates, S. P.; Hargreaves, R.; Fox, J. P.; Crain, J.; Finney, J. L.; Réat, V.; Soper, A. K. // Journal of Chemical Physics;10/1/2004, Vol. 121 Issue 13, p6456 

    An extensive series of neutron diffraction experiments and molecular dynamics simulations has shown that mixtures of methanol and water exhibit extended structures in solution despite the components being fully miscible in all proportions. Of particular interest is a concentration region...

  • Molecular nanostructures of alcohols adsorbed in micropores of active carbons. Tolmachev, A.; Khondar', G.; Kucherov, A.; Matveenko, A.; Fomkin, A. // Protection of Metals & Physical Chemistry of Surfaces;Mar2013, Vol. 49 Issue 2, p158 

    Quantitative topological analysis of molecular nanostructures of alcohols adsorbed in a model pore of active carbon depending on the micropore width and temperature is carried out. The analysis is performed using a method (MDTG) that we suggested earlier. It is based on a combination of...

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics