Debye

About: Debye is a research topic. Over the lifetime, 5339 publications have been published within this topic receiving 124744 citations. The topic is also known as: D.

Errata: The Intrinsic Viscosities and Diffusion Constants of Flexible Macromolecules in Solution

Abstract: A theory of the intrinsic viscosities and translational diffusion constants of flexible macromolecules is developed on the basis of the random coil model with hindered internal rotation. Proper account is taken of the hydrodynamic interaction of the monomer units of the molecule and of inhibited flow through the chain. The theory leads to results qualitatively similar to those obtained by Debye on the basis of a molecular model consisting of a sphere containing a uniform distribution of resisting points. However, significant quantitative differences between the two theories are found.

Electromagnetic Diffraction in Optical Systems. I. An Integral Representation of the Image Field

Abstract: An integral representation is obtained for the electromagnetic field in the image space of an optical system . This representation, which is not restricted to systems of low angular aperture, is in the form of an angular spectrum of plane waves, and is closely related to that introduced by Luneberg (1944) as a vector generalization of well-known formulae of Debye (1909) and Picht (1925). It is shown that the representation has a simple physical interpretation in terms of a modified Huygens—Fresnel principle which operates with secondary plane waves rather than with secondary spherical waves.

Equations for Calculating the Dielectric Constant of Saline Water (Correspondence)

Abstract: The dielectric constant of saline water may be represented by an equation of the Debye form. Equations for the parameters in the Debye expression are given as functions of the water temperature and salinity.

Ab initio calculations of elastic constants and thermodynamic properties of bcc, fcc, and hcp Al crystals under pressure

Abstract: We have performed ab initio electronic structure and total-energy calculations for bcc, fcc, and hcp Al structures to study the equations of state, volume dependences of elastic constants, and relative stability diagram for these structures. A technique for elastic constant calculation in the case of initial isotropic pressure is presented. In this study we used the accurate full-potential linear muffin-tin orbital method to describe electrons of the crystal and the Debye treatment of the vibrating lattice. The volume dependence of the Debye temperature is derived from the volume dependence of the elastic constants. Our calculations show that at pressures of 1–2 Mbar and temperatures of about 1000 K and higher, the aluminium structure must have a lower symmetry than the structures considered.

Calculated thermal properties of metals.

Abstract: The thermal properties of the 14 nonmagnetic cubic metals through the 4d transition series are derived from first-principles electronic-structure calculations coupled with a Debye treatment of the vibrating lattice. Debye temperatures and Gr\"uneisen constants are derived from an analysis of the compressional characteristics of rigid-lattice binding curves and are used to define the contribution of the lattice vibrations to the free energy. A minimization of the resulting free energy with respect to volume yields temperature-dependent lattice separations and coefficients of thermal expansion. Theoretical values of cohesive energies, equilibrium lattice separations, bulk moduli, Debye temperatures, Gr\"uneisen constants, and coefficients of thermal expansion are derived directly from computed electronic-structure results. Good agreement with experiment is found for all computed quantities.