In order to obtain more information on the development, morphology and function of the pores of Kohn, the lungs of Wistar rats are studied during their early postnatal period, up to 3 weeks of age, by scanning and transmission electron microscopy. The substantial development of the interalveolar pores on days 14 and 21 coincides with the period of septal rearrangement when secondary interalveol...

We provide a priori error estimates for the spectral and pseudospectral Fourier (also called planewave) discretizations of the periodic ThomasFermi-von Weizsäcker (TFW) model and for the spectral discretization of the Kohn-Sham model, within the local density approximation (LDA). These models allow to compute approximations of the ground state energy and density of molecular systems in the cond...

The year 2006 marks the 50th anniversary of the discovery of cellulose acetate (CA) electrophoresis by Joachim Kohn, a pathologist at Queen Mary's Hospital in Roehampton, London. During a career in pathology that began in 1950 and spanned 37 years, Kohn published more than 50 papers in clinical laboratory medicine. He was the first to report the use of CA microbiology filters as solid supports ...

A uni® ed review of various Kohn variational methods for scattering calculations is presented using appropriate Bloch operators. Previous expressions are generalized slightly to use either an in® nite range or a ® nite range of the scattering coordinate, or to use a basis set with non-® xed log derivative boundary conditions. A non-variationalmethod (method of moments) is used in the derivation...

I present the detailed behavior of phonon dispersion curves near momenta which span the electronic Fermi sea in a superconductor. I demonstrate that an anomaly, similar to the metallic Kohn anomaly, exists in a superconductor’s dispersion curves when the frequency of the phonon spanning the Fermi sea exceeds twice the superconducting energy gap. This anomaly occurs at approximately the same mom...

We develop the gentlest ascent dynamics for Kohn-Sham density functional theory to search for the index-1 saddle points on the energy landscape of the Kohn-Sham density functionals. These stationary solutions correspond to excited states in the ground state functionals. As shown by various examples, the first excited states of many chemical systems are given by these index-1 saddle points. Our ...

We calculate the exact Kohn-Sham potential that describes, within time-dependent density-functional theory, the propagation of an electron quasiparticle wave packet of nonzero crystal momentum added to a ground-state model semiconductor. The potential is observed to have a highly nonlocal functional dependence on the charge density, in both space and time, giving rise to features entirely lacki...

In Kohn–Sham density functional theory, only the highest occupied eigenvalue has a rigorous physical meaning, viz., it is the negative of the lowest ionization energy. Here, we demonstrate that for finite systems, the unoccupied true Ž . Kohn–Sham eigenvalues as opposed to the those obtained from the commonly used approximate density functionals are also meaningful in that good approximations t...

Atomic vibrations are partially screened by electrons. In a metal this screening can change rapidly for vibrations associated to certain points of the Brillouin zone, entirely determined by the shape of the Fermi surface. The consequent anomalous behaviour of the phonon dispersion is called Kohn anomaly. Graphite is a semimetal. Nanotubes can be metals or semiconductors. We demonstrate that two...