Anomalous Dielectric Dispersion Research Articles

Relaxor ferroelectric-like glassy dielectric dispersion in the triple perovskite Ba3CoSb2O9.

In this work, the dielectric response of polycrystalline Ba3CoSb2O9 was studied as a function of temperature (30 to 900 °C) and frequency (10 Hz to 10 MHz). The triple perovskite Ba3CoSb2O9 was successfully synthesized and characterized for structural and dielectric properties. The Rietveld analysis of the X-ray diffractogram confirms the formation of a hexagonal phase with P63/mmc symmetry. This centrosymmetric 3(BaCo1/3Sb2/3O3) perovskite shows structural similarity to a prototypical non-centrosymmetric relaxor ferroelectric, PbMg1/3Nb2/3O3. The dielectric constant, ε', follows a non-Debye Cole-Cole relation and exhibits anomalous responses such as: (a) a thermally activated colossal dielectric constant (>105) and (b) a highly dispersive peak maximum (523-853 K). The real part of ac conductivity, σ', also shows a change of approximately 6 orders in magnitude (10-8 to 10-2 S m-1). Validation of Jonscher's law and impedance (Nyquist plot) and modulus (M'') analyses indicate that hopping polarization is the predominant thermally activated mechanism. Moreover, the large value of ε' and its dispersion were found to be highly correlated with the underlying crystal structure and were attributed to the local ionic site ordering. The study suggests that the anomalous dielectric dispersion must have an intrinsic origin.

Succussed Serial Dilutions in Water Carry Solute Information via Solute-Specific Water Structures-A Theory Based on Quantum Electrodynamics.

Active ingredients are unlikely to be present in homeopathic dilutions that surpass the Avogadro limit. Yet responses of biological systems to these substances-chemically equivalent to water and indistinguishable from one another-are specific to the materials that are diluted away. This article addresses this challenging problem of homeopathy by identifying its underlying cause through a quantum electrodynamics-based "structural model" stated as: Succussed serial dilutions in water carry information about the solute via solute-specific water structures. The model is verifiable by our three-stranded set of experiments-nuclear magnetic resonance spectroscopy, anomalous dielectric dispersion, and atomic force microscopy. The results, some of which are presented here, directly or indirectly indicate that even extremely diluted solutions, devoid of any gross presence of the solutes, contain solute-reminiscent water structures. Apart from contributing to understanding high-dilution phenomena, these findings are expected to create an impact in the areas of medicine, pharmacopeia, and biology. Succussed aqueous dilutions acquire altered water structures with change of starting material: thus, their altered properties may be ascribed to these water structures, akin to allotropes of carbon. This theory justifies water structures as potential information carrier through succussed serial dilutions.

Simultaneous normal – Anomalous dielectric dispersion and room temperature ferroelectricity in CBD perovskite BaTiO3 thin films

Chemical bath deposition (CBD) method, being an electroless technique, is used to prepare phase pure barium titanate (BaTiO3) thin films using glass as substrate. Molarity of the solution is varied from 0.1 to 1.2 M, whereas, solution temperature is kept constant at 78 °C. XRD analyses show formation of perovskite tetragonal phase of BaTiO3 at all the molarities when films are annealed at 300 °C. Strengthening in perovskite tetragonal phase is observed with increase in solution molarity. Ellipsometric results show high transmission (∼ 83 %) in the visible region for thin films prepared with 1.2 M solution. Variation in direct band gap, 3.31–3.61 eV, is observed for annealed thin films. High dielectric constant (∼ 539.26 at log f = 3) and low tangent loss is obtained for 1.2 M based thin films. Thin films prepared under all the conditions show normal and anomalous / U-shaped frequency dependent dielectric response (i.e. ∼ 2754.24 at log f = 1.5 and ∼ 2004.73 at log f = 7.5). Maximum spontaneous polarization of ∼ 14.78 μC/cm2 and remnant polarization of ∼ 6.94 μC/cm2 are observed for 1.2 M sample. It is important to mention here that U-shaped high dielectric and good ferroelectric properties of BaTiO3 are observed in current study with no change in perovskite structure of tetragonal phase making it a potential candidate for storage devices at low and high frequencies.

Dielectric dispersion studies of some potentised homeopathic medicines reveal structured vehicle

Avogadro's Number gives 12c as the limit beyond which no original substance can be present in a highly diluted and succcussed (potentised) homeopathic medicine, implying that chemically such dilutions consist of nothing but the vehicle. But there is evidence that living systems react to homeopathic medicines diluted even above 12c. To explain how such medicines differ from another I hypothesise that altered structure may cause the difference, such as that between diamond and amorphous carbon. Some scientists have argued that dilution followed by succussion may lead to altered structural arrangement of water molecules. This concept may be termed 'Induced Molecular Structure'. Dielectric dispersion studies were conducted in a broad range with potencies below and above the Avogadro limit by taking 6c and 30c potencies of Graphites and Cuprum Metallicum in liquid form. Measurements were made with an Anomalous Dielectric Dispersion Detector (A3D), an instrument developed by the author. Experiments were carried out in a frequency range of 100kHz to 50MHz. Shifting of resonance frequencies as a function of medicine and potency, with potencies below and above the Avogadro limit, was observed. The range of resonance frequencies suggest that the phenomenon might originate from oscillation of dipoles caused by electric field in variously structured and polarised water. Also, there is reasonable evidence that frequencies change with materials and potency.

Dielectric Dispersion Studies Indicate Change in Structure of Water by Potentised Homeopathic Medicines

Response of living bodies to different vastly ‘diluted’ homeopathic medicines are different (rejecting the sceptic’s view of ‘placebo’ effect), though they are chemically same. Till now there is no satisfactory answer to how one such medicine differs from another in terms of scientifically measurable parameters. This paper tries to address this basic issue by taking two medicines of the same potency and two different potencies of the same medicine, namely, Arnica Mont 30c, 200c and Anacardium Orient 30c, 200c. These potencies are well above the Avogadro limit. The investigation reported here proceeds with the concept of ‘induced molecular structure’ advanced by a number of scientists. Dielectric dispersion is used as the tool for experimental verification. It is based on the fact that when the exciting frequency of applied electric field equals the characteristic frequency, then macromolecules resonate leading to anomalous dielectric dispersion associated with sharp increase in dielectric loss, the resonance frequencies being different for macromolecules of different structures or dimensions. The results suggest that medicine- and potency-specific attributes are acquired by the vehicle (i.e. water) in the form of macromolecules generated by the potentization process of homeopathy making one medicine structurally different from another.

Theory and Instrumentation Related to Potentised Homoeopathic Medicines∗†

This paper offers a theory for establishing the scientific basis of homoeopathic medicines followed by an instrumentation technique named as ′dielectric dispersion of ordered molecular groups of sugar of milk caused by potentised homoeo - medicines for verification of the proposed theory. Usually one studies anomalous dielectric dispersion of a material caused by intra-molecular binding forces of separate molecules. The authors of this paper extend this concept to ordered molecular groups. The theoretical analysis suggests that there will be anomalous dielectric dispersion at selected frequencies specific to shape, size and number of atoms in the ordered molecular group of the material. Now, homoeopathic medicines, as is felt by several modern investigators including the authors of this paper, are ordered molecular groups of the vehicle of potentisation. The instrumentation method, supported by the properly developed theory mentioned above, is described in this paper to observe the frequency domain signature of the sugar of milk soaked with homoeopathic medicine. The anomalous dielectric dispersion of the medicine-soaked sugar of milk, which occurred at acoustic resonant frequencies of the material, were observed repeatedly and recorded through the experimental arrangement. The results were further confirmed by blind experiments. Thus the experiments validate the theoretical model. Further, the experimental results and the nature of results obtained from MATLAB - simulation support each other giving additional confidence in the approach.

Anomalous Dielectric Dispersion in Tantalum Oxide Films Prepared by RF Sputtering

Tantalum oxide thin films prepared by rf sputtering show anomalous dielectric dispersion in the low frequency range. Very high dielectric constant and dielectric loss (tan δ) are observed in the frequency range below 10 kHz. The dielectric loss (tan δ) peak shifts toward higher frequencies with temperature. In addition, this peak shows strong thickness dependence which excludes the possibility of ordinal dipolar polarization. These characteristics are explained in terms of interfacial polarization based on the Maxwell-Wagner mechanism. The thickness of the aluminum oxide blocking layer on the electrode surface has been evaluated to be approximately 38 nm from experimental results.

Anomalous dispersion in the dielectric spectra of conductive materials

A high-frequency impedance analyzer is used to study the dielectric permittivity of a conductor-filled composite. An anomalous dielectric dispersion is observed at high frequencies. Comparison to dielectric probe measurements indicates that this dispersion is not reproducible with other measurement techniques and may be a result of instrumental artifacts. Theoretical circuit models show that this dispersion is most likely caused by finite inductances and resistances that exist in the electrode fixture.

Anomalous dielectric dispersion observed in trimethyleneglycol-water mixtures around melting point

Abstract Complex dielectric constants of trimethylene-glycol change drastically around the melting point. This change is closely related with the transfer from glassy state to non-glassy state and so with the change of relaxation mechanism in supercooled liquids.

Acceleration of dielectric relaxation by KOH-doping and phase transition in ice Ih

Dielectric properties of polycrystalline ice Ih doped with KOH were investigated at low temperatures. The dielectric relaxation was drastically accelerated by KOH-doping. An order-disorder phase transition below which the protons are ordered was observed at 72 K. The anomalous dielectric dispersion in the low temperature phase and the origin of the acceleration of the dielectric relaxation are discussed.

Ultra-thin Layer of Lipids in Polymer Film and Its Electric Properties. New Sorption Method to Prepare a Model Biomembrane System

Abstract The ultra-thin layer of glycerol α-cis-9-octadecenate (glycerol α-monooleate:GMO) could be formed by impregnating nitrocellulose (NC) film with GMO and by then filling microscopically the interstices of the network structure of NC with microdrops of GMO. The dielectric dispersion characteristic of this film was found to be similar to that observed for bimolecular films. In a concentrated KCl solution (100 mM), however, an anomalous dielectric dispersion phenomenon was observed below 10 kHz. The low-frequency dispersion was attributed to surface conductance along the planes of contact between the GMO microdrops and the NC network. The ultra-thin film of di(cis-9-octadecenyl)phosphate (dioleyl phosphate: DOPH) could also be formed by this method. When a constant DC voltage (50 mV) was applied across the film in a 20 mM KCl solution, the electric current through the whole system changed periodically.

Anomalous Dielectric Dispersion in Glasses at Low Temperatures

We have found a strong temperature dependence in the dielectric constant of three different glasses below 5 K, which we ascribe to the low-energy excitations of the amorphous state. From our data we can determine the electrical dipole moment associated with these excitations, which gives rise to resonant absorption of electromagnetic waves. The corresponding absorption coefficient is expected to saturate at electromagnetic intensities above a few milliwatts per square centimeter.

Dielectric evidence of molecular rotation in solids∗

Measurements of dielectric constant as a function of temperature give clear evidence of molecular rotation in many crystalline phases comparable to the rotation in liquids and in a few organic glasses which have been studied. The effect of molecular shape upon rotation is examined, it being shown that spheroidal and cylindrical molecules may rotate. The rotation may be presumed usually to consist of rotational jumps between potential energy minima. Rotational freedom depends upon the closeness of the approach to one of the ratios of the molecular radii in different directions, but is influenced by the closeness of the molecular packing. Many solids which show a rotational transition point are soft, waxy, and translucent in this rotator phase between the transition point and the melting-point and brittle below the transition point. A number of solids which show anomalous dielectric dispersion like that found in liquids and organic glasses, but no rotational transition, are brittle. It appears that plasticity may result from the increase in volume per molecule occurring when slightly unsymmetrical molecules begin to rotate at a transition point. Dielectric relaxation measurements show that the internal friction resisting molecular rotation in the crystal is, in some cases, about the same as in the liquid state, and, in some cases, much less.

Hydrogen Bonding and Anomalous Dielectric Dispersion in Long-chain Alcohols and Mercaptans1

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHydrogen Bonding and Anomalous Dielectric Dispersion in Long-chain Alcohols and Mercaptans1Armand Di Giacomo and Charles P. SmythCite this: J. Am. Chem. Soc. 1956, 78, 10, 2032–2035Publication Date (Print):May 1, 1956Publication History Published online1 May 2002Published inissue 1 May 1956https://doi.org/10.1021/ja01591a002RIGHTS & PERMISSIONSArticle Views53Altmetric-Citations7LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (409 KB) Get e-Alerts Get e-Alerts

A New Dielectric Dispersion in Long-Chain Normal Primary Alcohol of Probable Carbon Number 32 at Lower Temperature Phase

Certain normal long-chain alcohols are well known for their anomalous dielectric properties in higher temperature phase, which are often attributed to molecular rotation in the crystal lattice. In the present article are described the experiments on the anomalous dielectric dispersion of long-chain normal primary alcohol of probable carbon number 32, extracted from Carnauba wax. The higher temperature phase (68°–86°C) has quite the same dielectric behaviour which is already known in hexadecyl and octadecyl alcohol. But on the other hand, in lower temperature phase a new dispersion of Debye type was observed. The relaxation time seems to have a certain distribution, and the activation energy estimated from relaxation time versus inverse absolute temperature curve is 26.4 Kcal/mol. The dispersion is considered to be due to the reorientation of O–H group as a result of the restricted rotation or twisting of the molecule.