Semiclassical results in the linear response theory

We consider a quantum system of non-interacting fermions at temperature T, in the framework of linear response theory. We show that semiclassical theory is an appropriate framework to describe some of their thermodynamic properties, in particular through asymptotic expansions in ? (Planck constant) of the dynamical susceptibilities. We show how the closed orbits of the classical motion in phase space manifest themselves in these expansions, in the regime where T is of the order of ?.     

Cyclization reactions of quaternary salts of azaaromatics

Cyclization reactions of quaternary salts of azaaromatics including inter- and intramolecular condensation as well as radical processes are described.Institute of Chemistry, Pedagogical University, Czestochowa, Poland. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 23–40, January, 1997.     

A short large scale synthesis of (±) sarkomycin esters

(±) Sarkomycin ethyl ester has been prepared in four steps from ethyl acrylate.     

Stereochimie de la reaction de rupture par le brome de la liaision siliciumaryle du dimethyl-1,2 phenyl-1 silacyclopentane

Stereospecific synthesis of geometric isomers of 1,2-dimethyl-1-phenylsilacyclopentane is described. We demonstrate that brominolysis of the arylsilicon bond occurs with predominant inversion of configuration at the silicon atom of the silacyclopentane ring.     

Etudes stereochimiques dans la serie du silacyclopentane: synthese de dimethyl-1,2 alcoxy-1 silacyclopentanes a stereoisomere preferentiel

The stereoselective alcoholysis of 1,2-dimethyl-1-chlorosilacyclopentane and the catalytic alcoholysis of 1,2-dimethylsilacyclopentane are described.     

Hétérocycles contenant du phosphore. XXXII. Etude de l'action des phosphorhydrazides sur les orthoesters,l'anhydride acétique et l'acide formique

The reaction of phosphodi- or trihydrazides with orthoesters affords mainly 2,3,4,5-tetrahydro-1,2,4,5,3-tetrazaphosphorines and sometimes 4-amino-1,2,4,3-triazaphospholidines. These 1,2,4,5,3-tetrazaphosphorines present a prototropy which explains different pathways of the reaction of these derivatives with formaldehyde or acetone, The structure of all heterocycles which were obtained was established by nmr spectra.     

Theory of dressed-excitons

We show that the exciton optical Stark effect is basically a dressed-exciton effect: excitons are dressed by the electromagnetic field in a way similar to the way atoms are dressed. The situation appears, however, much richer in semiconductor than in atomic physics due to both the complexity of the band structure and the Coulomb interaction between excitons. We show that the dressed-exciton effect can appear as either a blue or a red shift of the exciton line as well as a splitting of exciton levels, with an interesting dimensional effect in the absorption strength. We also relate the dressed-exciton to the polariton effect.