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Journal ArticleDOI

Dielectric Properties of Liquid Butyl Alcohols

01 Oct 1955-Journal of Chemical Physics (AIP Publishing)-Vol. 23, Iss: 10, pp 1762-1766
TL;DR: In this paper, the temperature dependences of static values are examined in terms of finite extent of chainwise molecular coordination by hydrogen bonding, and the rate laws of the dispersions are discussed.
Abstract: Measurements of static dielectric constant were made for all except t‐butyl alcohol from the boiling points to —140°C; dispersion and loss were measured below 0°C in the range 20 cy/sec to 2 Mc/sec. Multiple dispersions were found as in other alcohols. The temperature dependences of static values are examined in terms of finite extent of chainwise molecular coordination by hydrogen bonding, and the rate laws of the dispersions are discussed.
Citations
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Journal ArticleDOI
TL;DR: In this article, a broad correlation of non-debye behavior with non-Arrhenius relaxations was found for different types of glass formers, distinguished by their respective molecular complexity.
Abstract: Deviations from thermally activated and from exponential response are typical features of the vitrification phenomenon and previously have been studied using viscoelastic, dielectric, calorimetric, optical, and other techniques. Linear response data from literature on about 70 covalent glass formers, ionic melts, supercooled liquids, amorphous polymers, and glassy crystals are surveyed. Except for orientational glasses and monohydric aliphatic alcohols a distinct but broad correlation of non‐Debye behavior with non‐Arrhenius relaxations is found. Within the broad trend several groups of materials, distinguished by their respective molecular complexity, can be identified and are shown to exhibit narrow correlations. At a given degree of deviation from Arrhenius behavior externally imposed stresses are relaxed with a departure from exponential behavior which is stronger the more the molecular or atomic subunits of the glassforming material are interconnected with each other.

2,146 citations

Journal ArticleDOI
TL;DR: A brief review of the progress made in the study of relaxations of molecular liquids near and below the glass transition temperature in the context of present theories of glass structure, as well as some new results on the relaxation of rigid molecular liquids and plastic crystalline solids.
Abstract: It has been known for many years that substances in the glassy state retain some degree of molecular mobility that is detectable by a dielectric or a mechanical relaxation, or by an N M R experiment. These relaxations have been termed secondary or p relaxations and they occur on a time scale many times shorter than that of the main relaxation responsible for the glass transition itself.' The presence of such relaxations has generally been associated with the motion of a side group attached to a polymer chain, o r with a certain type of movement of the chain itself, and has been explained in terms of hindered internal molecular modes of motion that remain active even when the molecule as a whole is frozen in place in a glassy matrix.' Several years ago we studied a number of glasses made from molecular liquids2 lacking either a side chain or any other internal degree of freedom capable of giving rise to a relaxation traditionally invoked for polymers and network glasses. The study revealed a remarkable similarity in the dielectric relaxations of these glasses to those of polymers, and a surprisingly uniform pattern of behavior. The main conclusion drawn from the study was that the molecular mobility seen as p relaxations is intrinsic to the nature of the glassy state. It became apparent then that a theory for the structure of grossly disordered solids must necessarily consider such relaxations as arising from a motion over the potential energy barriers similar in origin to those involved in the glass transition itself. There is, however, another approach to the study of grossly disordered solids, such as glasses. One may start from a perfect crystal, relatively well understood both theoretically and experimentally because the translational symmetry allows enormous simplification of the algebra, and approach the glassy state gradually. An orientationally disordered or plastic crystal is intermediate between a perfect crystal and a glass in that, although there is a long-range order of molecular positions, there is no long-range order in the molecular orientations. This paper presents a brief review of the progress made in the study of relaxations of molecular liquids near and below the glass transition temperature in the context of present theories of glass structure, as well as some new results on the relaxation of rigid molecular liquids and plastic crystalline solids, and the implication these results have for the concepts of the glass transition phenomenon.

381 citations

Journal ArticleDOI
TL;DR: In this article, the dielectric permittivity and the Dielectric loss factor of 5 methyl-3, 4 methylmethyl-3 and 3 methylpentane were measured from 50 to 105 Hz and from −196 to about 20°C above their respective glass transition temperatures.
Abstract: The dielectric permittivity and the dielectric loss factor of 5‐methyl‐3, 4‐methyl‐3 and 3‐methyl‐3‐heptanol, n‐ and iso‐butanol, 1,2‐propanediol, dimethyl and diethyl phthallate, and 3‐methylpentane have been measured from 50 to 105 Hz and from −196 to about 20°C above their respective glass transition temperatures. The glass transition temperature Tg of these substances, several more isomeric octanols, and 1‐phenyl‐1‐propanol have been measured by differential thermal analysis. All substances except for 3‐methylpentane and iso‐butanol show either a well‐defined secondary relaxation peak in tanδ, or a clear indication of the presence of a secondary relaxation below their Tg's. Arrhenius plots for the α‐relaxation process of the isomeric octanols are linear with an activation energy of 16–18 kcal/mole, while for other substances they are nonlinear with the activation energy changing from 30 to 70 kcal/mole. The Arrhenius plots for the secondary relaxations are linear and have an activation energy of 4–8 k...

351 citations

Journal ArticleDOI
TL;DR: In this article, the authors derived simple expressions relating the hydrogen bond thermodynamic properties to the static dielectric constant of water, taking into account the dipolar correlations between a central molecule and H-bonded neighbors present in infinite number of shells surrounding the central molecule.
Abstract: We apply statistical mechanical principles to derive simple expressions relating the hydrogen bond thermodynamic properties to the static dielectric constant of water. The approach followed by us was to develop an expression for the Kirkwood’s structure factor (g) of water, taking into account the dipolar correlations between a central molecule and H-bonded neighbors present in infinite number of shells surrounding the central molecule. The number of H-bonded neighbors in a specific shell was related to the probability P for the various donor/acceptor sites of any given water molecule to be associated. Neglecting cooperativity effects, we evaluated P by focusing only on the correct counting of H-bonds formed between various association sites rather than on the oligomer distribution. The theory yielded an extremely simple expression for the structure factor (g) of the fluid at any given temperature in terms of the enthalpy (H) and entropy (S) changes associated with bond formation. The proposed theory was then combined with the Kirkwood–Frohlich theory for evaluating the dielectric constant (e0). We have demonstrated that the theory correctly predicts the dielectric constant of ice-I without the use of any adjustable parameters. We have then deduced estimates for H-bond thermodynamic properties (H=−5.58 kcal/mole of H-bonds; S=−8.89 cal/deg⋅mole of H-bonds) by fitting the theoretical results for e0 of liquid water to available experimental data over temperatures ranging from 0 °C to the critical point of water. The error in the theoretical values was found to be within 1% of the corresponding experimental values over the entire range of temperatures studied. To further test the theory, we have demonstrated that the temperature variation of the average number of H-bonds per water molecule, calculated using the proposed theory with the above mentioned values for H and S, compares quite well with those estimated from various available spectroscopic and molecular simulation studies.

268 citations

Journal ArticleDOI
TL;DR: In this article, Debye devised a relaxation model for application to the dielectric properties of water and alcohols, which has been studied extensively because they are vital for biophysical processes, of fundamental importance as solvents in industrial processes and in every-day use.

221 citations


Cites background or result from "Dielectric Properties of Liquid But..."

  • ...In 1951, Davidson and Cole [18] noted that while the Debyemodel is able to describe the frequency dependent dielectric loss formonohydroxy alcohols it fails for poly-alcohols thereby confirming earlier observations [19]....

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  • ...Also in 1955, Dannhauser and Cole [22] modified the model of Oster and Kirkwood [15] by assuming that monohydroxy...

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  • ...From today’s point of view, this analysis is biased by the fact that only Debye type peaks were considered for the superposition that represents the entire loss profile, whereas a single Cole–Cole or Cole–Davidson function could be appropriate for describing the loss that is in excess of the prominent Debye peak [166]....

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  • ...Both Cole–Cole and Cole–Davidson type fit functions have been used with success to describe this peak, with the uncertainty originating from the overlap with the typically much more intense Debye process on the low-frequency side of peak II....

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  • ...In the same work Davidson and Cole estimated the hydrodynamic volumes for propanol, propylene glycol, and glycerol....

    [...]

References
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Journal ArticleDOI
TL;DR: In this paper, an extension of the Onsager theory of dielectric polarization is presented, which is applied to liquid water under the assumption of tetrahedral coordination and directed bonds between neighboring molecules.
Abstract: An extension of the Onsager theory of dielectric polarization is presented. The local dielectric constant is approximated by the macroscopic dielectric constant of the fluid in a region outside a molecule and its first shell of neighbors rather than in the entire region exterior to the molecule. In addition to the molecular dipole moment, the average value 〈cosγ〉Av of the cosine of the angle between neighbor dipoles is a determining factor. Hindered relative rotation of neighboring molecules produces a correlation between their orientations and prevents 〈cosγ〉Av from vanishing. The theory is applied to liquid water under the assumption of tetrahedral coordination and directed bonds between neighboring molecules.

1,660 citations

Journal ArticleDOI
TL;DR: The theory of dielectric polarization of polar liquids is used to calculate the dielectrics constants of water and some alcohols as mentioned in this paper, which is closely related to the thermodynamic ''abnormality'' of polar liquid.
Abstract: The theory of dielectric polarization of polar liquids is used to calculate the dielectric constants of water and some alcohols. Quasi‐rigid coordination models, based upon x‐ray structural investigations, are employed in the calculation of a function g which measures the orientational correlation between neighbors in the liquid. It is pointed out that the correlation function g is closely related to the thermodynamic ``abnormality'' of polar liquids.

214 citations

Journal ArticleDOI
TL;DR: In this paper, dielectric constants and loss were measured from room temperature to 160°C for the pure liquids and mixtures with small amounts of water to facilitate supercooling, and two distinct dispersion regions were found below −100°C in the experimental frequency range from 1 cy/sec to 5 Mc/sec.
Abstract: Dielectric constants and loss were measured from room temperature to —160°C for the pure liquids and mixtures with small amounts of water to facilitate supercooling. Two distinct dispersion regions were found below —100°C in the experimental frequency range from 1 cy/sec to 5 Mc/sec. The temperature dependences are similar and described by rate laws of the form found for similar measurements in 1‐propanol. An explanation of the multiple dispersions in terms of hydrogen bond breaking to permit reorientation of alkyl and hydroxyl groups is discussed.

171 citations

16 Nov 1953
TL;DR: In this paper, the authors measured the dielectric constants of liquid EtOH and 2-PrOH from room temperature to -160 deg C for pure liquids and mixtures with small amounts of H2O to facilitate supercooling.
Abstract: : Dielectric constant and loss measurements of liquid EtOH and 2-PrOH were obtained from room temperature to -160 deg C for the pure liquids and mixtures with small amounts of H2O to facilitate supercooling. Two distinct dispersion regions were found below -100 deg C in the range from 1 c to 5 mc. The temperature dependances were similar and described by rate laws of the form found for similar measurements in 1-PrOH. The magnitudes and temperatures dependances of the equilibrium dielectric constants are discussed in terms of Kirkwood's theory. An explanation of the multiple dispersions is discussed in terms of H bond breaking to permit reorientation fo alkyl and hydroxyl groups. The dielectric constants and loss of trimethylene glycol were measured in the range 1 to -70 deg C at frequencies below 5 mc. The results indicate that the complex dielectric constant is not represented by a Debye function, but can be fitted by an empirical dispersion function of the same form describing measurements for glycerol and propylene glycol. The measured properties are intermediate between those for the latter 2.

157 citations