Topic
Debye model
About: Debye model is a research topic. Over the lifetime, 7462 publications have been published within this topic receiving 133987 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this paper, the role of ZnO on the structure of the investigated glass system was investigated using X-ray and FT-IR spectroscopic studies, and the results indicated that Zinc ions have been substituted for boron ions as tetrahedral network former ions.
133 citations
TL;DR: In this paper, it was shown that the specific heat of graphite varies as T2 instead of T3 between 15°K and 80°K, and that such a behavior is a consequence of the elastic anisotropy of the graphite, and therefore an intrinsic property, rather than a particle size effect as suggested by Gurney, or a plate-like behavior.
Abstract: Recent experiments have shown that the specific heat of graphite varies as T2 instead of T3 between 15°K and 80°K. In this paper such a behavior is shown to be a consequence of the elastic anisotropy of graphite, and therefore an intrinsic property, rather than a particle size effect as suggested by Gurney, or a plate‐like behavior as suggested by Komatsu and Nagamiya. The Gurney treatment is shown to be in error both as to the enumeration of modes, and as to the temperature range over which the particle size effect might be of significance. The Komatsu and Nagamiya treatment is shown to be inconsistent with elasticity theory. The present treatment employs a semirigorous analysis of the normal mode problem for the transverse vibrations, approximated for long wavelengths. It is found that experimental data from 15–1000°K can be well fitted by dividing the lattice vibrations into two types: (a) modes with atom displacements normal to the layer planes with a Debye temperature of 900°K, and (b) modes with ato...
132 citations
TL;DR: In this article, the frequency-dependent absorption coefficient and index of refraction in the far-infrared region of the spectrum for mixtures of acetonitrile and water were reported.
Abstract: We report the frequency-dependent absorption coefficient and index of refraction in the far-infrared region of the spectrum for mixtures of acetonitrile and water. The mixtures do not behave ideally, and deviate from ideality most noticeably for mixtures that are between 25% and 65% acetonitrile by volume. Two implementations of the Debye model for describing the dielectric relaxation behavior of mixtures are compared, and we show that these mixtures are better treated as uniform solutions rather than as two-component systems. We find an enhanced structure in the mixtures, relative to ideal mixtures, but we do not find direct evidence for microheterogeneity. The Debye time constant for the primary relaxation process for the mixtures is up to 25% longer than that for an ideal mixture.
132 citations
TL;DR: In this paper, the room temperature and low temperature elastic properties of hexagonal C40 transition metal disilicides, NbSi2 and TaSi2, have been studied using Resonant Ultrasound Spectroscopy (RUS).
132 citations
TL;DR: It is reported for the first time that a buckled structure has three conflicting effects: increasing the Debye temperature by increasing the overlap of the pz orbitals, suppressing the acoustic-optical scattering by forming an acoustic- optical gap, and increasing the flexural phonon scattering.
Abstract: Controlling heat transport through material design is one important step toward thermal management in 2D materials. To control heat transport, a comprehensive understanding of how structure influences heat transport is required. It has been argued that a buckled structure is able to suppress heat transport by increasing the flexural phonon scattering. Using a first principles approach, we calculate the lattice thermal conductivity of 2D mono-elemental materials with a buckled structure. Somewhat counterintuitively, we find that although 2D group-V materials have a larger mass and higher buckling height than their group-IV counterparts, the calculated κ of blue phosphorene (106.6 W mK−1) is nearly four times higher than that of silicene (28.3 W mK−1), while arsenene (37.8 W mK−1) is more than fifteen times higher than germanene (2.4 W mK−1). We report for the first time that a buckled structure has three conflicting effects: (i) increasing the Debye temperature by increasing the overlap of the pz orbitals, (ii) suppressing the acoustic–optical scattering by forming an acoustic–optical gap, and (iii) increasing the flexural phonon scattering. The former two, corresponding to the harmonic phonon part, tend to enhance κ, while the last one, corresponding to the anharmonic part, suppresses it. This relationship between the buckled structure and phonon behaviour provides insight into how to control heat transport in 2D materials.
132 citations