Dielectric relaxation spectroscopy of 2-propanol-water mixtures

The complex dielectric spectra of 2-propanol–water mixtures were determined at seven molar fractions of 2-propanol, X=0.03, 0.065, 0.14, 0.3, 0.5, 0.7, and 0.9 at 25 °C in the frequency range 0.1⩽ν/GHz⩽89 with the help of time domain reflectometry in 0.1⩽ν/GHz⩽25 and waveguide interferometry in 13⩽ν/GHz⩽89. In the alcohol-rich region of 0.3⩽X⩽1.0, a description of the e*(ν) spectra requires the superposition of the three relaxation processes. The dominating low-frequency dispersion (j=1) follows a Cole–Cole equation. Additionally, two Debye equations (j=2 and 3) with the relaxation times of τ2∼10–20 ps and τ3∼1–2 ps are required to fit the high-frequency part of the spectrum. The three processes are assigned to the cooperative dynamics of the H-bond system (j=1), a rotation of singly H-bonded alcohol monomers at the ends of chainlike structure (j=2), possibly connected to the formation of bifurcate hydrogen bonds, and a flipping motion of free OH group (j=3). In the region of X<0.3, the intermediate alcoh...

[1]  J. Yarwood,et al.  FT-far-infrared spectroscopic studies of solute-solvent interactions and molecular dynamics in solutions of methanol, N-methyl formamide and N,N-dimethyl formamide , 1988 .

[2]  R. Nozaki,et al.  Broadband complex permittivity measurements by time-domain spectroscopy , 1990 .

[3]  Takaaki Sato,et al.  Dynamical aspects of mixing schemes in ethanol-water mixtures in terms of the excess partial molar activation free energy, enthalpy, and entropy of the dielectric relaxation process , 1999 .

[4]  D. D. Yue,et al.  Theory of Electric Polarization , 1974 .

[5]  U. Kaatze,et al.  Water−Ethanol Mixtures at Different Compositions and Temperatures. A Dieletric Relaxation Study , 2000 .

[6]  C. P. Smyth,et al.  Microwave Absorption and Molecular Structure in Liquids. LXII. The Three Dielectric Dispersion Regions of the Normal Primary Alcohols1 , 1965 .

[7]  U. Kaatze,et al.  The Complex Dielectric Spectrum of Aqueous Methanol and Isopropanol Solutions , 1989 .

[8]  Richard Buchner,et al.  Dielectric spectra of some common solvents in the microwave region. Water and lower alcohols , 1990 .

[9]  P. Sipos,et al.  Dielectric Relaxation of Dilute Aqueous NaOH, NaAl(OH)4, and NaB(OH)4 , 1999 .

[10]  H. Eugene Stanley,et al.  Network defects and molecular mobility in liquid water , 1992 .

[11]  Peter G. Wolynes,et al.  Large local energy fluctuations in water. II. Cooperative motions and fluctuations , 1988 .

[12]  J. Barthel,et al.  The dielectric relaxation of water between 0°C and 35°C , 1999 .

[13]  Takaaki Sato,et al.  Hydrophobic hydration and molecular association in methanol-water mixtures studied by microwave dielectric analysis , 2000 .

[14]  R. Richert,et al.  Dynamics of glass-forming liquids. III. Comparing the dielectric α- and β-relaxation of 1-propanol and o-terphenyl , 1997 .

[15]  J. Barthel,et al.  Dynamics of methanol-tetrachloromethane mixtures―A dielectric relaxation study , 1992 .

[16]  J. K. Vij,et al.  The exponential dielectric relaxation dynamics in a secondary alcohol’s supercooled liquid and glassy states , 2000 .

[17]  G. W. Euliss,et al.  Dynamic light scattering studies of concentration fluctuations in aqueous t‐butyl alcohol solutions , 1984 .

[18]  Y. Koga,et al.  Excess partial molar free energies and entropies in aqueous tert-butyl alcohol solutions at 25.degree.C , 1990 .

[19]  L. Saiz,et al.  Dielectric properties of liquid ethanol. A computer simulation study , 2000 .

[20]  U. Kaatze Dielectric relaxation of H2O/D2O mixtures , 1993 .

[21]  S. Mashimo,et al.  High order and local structure of water determined by microwave dielectric study , 1993 .

[22]  Y. Koga,et al.  Vapour pressure of aqueous tert.-butanol in the water-rich region: transition in the mixing scheme , 1990 .

[23]  Sandro L. Fornili,et al.  Hydrogen bond cooperativity in simulated water: Time dependence analysis of pair interactions , 1989 .

[24]  E. Hawlicka,et al.  Molecular dynamics studies of NaCl solutions in methanol–water mixtures.: An effect of NaCl on hydrogen bonded network , 1998 .

[25]  U. Kaatze Complex Permittivity of Water as a Function of Frequency and Temperature , 1989 .

[26]  Christopher C. Davis,et al.  Microwave dielectric characterization of binary mixtures of water, methanol, and ethanol , 1996 .

[27]  C. Haynes,et al.  Mixing scheme of aqueous butan-1-ol in the water-rich region at 25°C: Excess chemical potential, partial molar enthalpy, entropy and volume, heat capacity compressibility and thermal expansivity , 2000 .

[28]  G. P. Johari,et al.  Effects of induced steric hindrance on the dielectric behavior and H bonding in the supercooled liquid and vitreous alcohol , 2001 .

[29]  Takaaki Sato,et al.  Dielectric relaxation mechanism and dynamical structures of the alcohol/water mixtures , 2002 .

[30]  Richard Buchner,et al.  A computer-controlled system of transmission lines for the determination of the complex permittivity of lossy liquids between 8.5 and 90 GHz , 1991 .

[31]  Glenn Hefter,et al.  Dielectric relaxation of aqueous NaCl solutions , 1999 .

[32]  Takaaki Sato,et al.  Composition-dependent dynamical structures of 1-propanol–water mixtures determined by dynamical dielectric properties , 2000 .

[33]  Harald Redlin,et al.  Structures of water and primary alcohol studied by microwave dielectric analyses , 1991 .

[34]  G. Hefter,et al.  ION-PAIR AND SOLVENT RELAXATION PROCESSES IN AQUEOUS NA2SO4 SOLUTIONS , 1999 .

[35]  Richard Buchner,et al.  High frequency permittivity and its use in the investigation of solution properties , 1991 .

[36]  Noam Agmon Tetrahedral Displacement: The Molecular Mechanism behind the Debye Relaxation in Water , 1996 .

[37]  Hideki Tanaka,et al.  Fluctuation, relaxations, and hydration in liquid water. Hydrogen-bond rearrangement dynamics , 1993 .

[38]  U. Kaatze,et al.  DIELECTRIC RELAXATION OF H-BONDED LIQUIDS. MIXTURES OF ETHANOL AND N-HEXANOL AT DIFFERENT COMPOSITIONS AND TEMPERATURES , 1999 .

[39]  Takaaki Sato,et al.  Dynamical structure of oligo(ethylene glycol)s-water solutions studied by time domain reflectometry , 1998 .

[40]  M. Eid,et al.  Dielectric Behaviour of Some Pure Normal Alcohols and their Binary Mixtures , 1998 .

[41]  Fumio Hirata,et al.  Structure of tert-Butyl Alcohol−Water Mixtures Studied by the RISM Theory , 2002 .

[42]  J. Barthel,et al.  A time domain reflectometer for dielectric relaxation spectroscopy of electrolyte solutions , 1997 .

[43]  Takaaki Sato,et al.  Composition-dependent dynamical structures of monohydric alcohol-water mixtures studied by microwave dielectric analysis , 2002 .

[44]  G. Walrafen,et al.  Temperature dependence of the low‐ and high‐frequency Raman scattering from liquid water , 1986 .

[45]  J. Barthel,et al.  9 Dielectric relaxation in solutions , 2001 .

[46]  So,et al.  INVESTIGATION OF THE TEMPERATURE DEPENDENCE OF DIELECTRIC RELAXATION IN LIQUID WATER BY THZ REFLECTION SPECTROSCOPY AND MOLECULAR DYNAMICS SIMULATION , 1997 .

[47]  Hideki Tanaka,et al.  Large local energy fluctuations in water , 1987 .

[48]  C. Angell,et al.  Formation of Glasses from Liquids and Biopolymers , 1995, Science.

[49]  R. Richert,et al.  Dynamics of glass-forming liquids. II. Detailed comparison of dielectric relaxation, dc-conductivity, and viscosity data , 1996 .