Hyperchromats with linear dependence of longitudinal chromatic aberration on wavelength

Optical lens systems that are characterized by a chromatic aberration of a predefined form are called hyperchromats. Our work describes a theory of hyperchromats with a linear dependence of longitudinal chromatic aberration on wavelength. The equations are derived for calculation of basic design parameters of these optical systems and some examples of hyperchromatic optical systems are shown. Mentioned optical systems can be used especially in 3D imaging systems and confocal microscopy.     

From the Arrhenius to the Clausius–Clapeyron Equation

The dynamical nature of chemical equilibrium and the relationship between kinetics and thermodynamics are illustrated by the example of a pure liquid that is in equilibrium with its vapor.     

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Ultraviolet photoelectron spectra of gas phase and condensed tin and lead dihalides (MX2 ; M = Sn,Pb; X = Cl,Br, I)

The photoelectron spectra and electronic structures of the methylene dihalides, CH₂X₂ (X = F, Cl, Br and I), have been calculated by the overtapping-spheres SCF-Xα-MS method. The results are in good agreement with experimental data. Calculated assignments of the spectra are also presented and interpreted by assuming interaction between lone-pair and bonding orbitals.     

Least-squares fitting of wavefront using rational function

This paper describes a mathematical method for approximation of the measurement data in optical testing techniques. Presented method uses a least-squares fit of two-dimensional rational function model to interferometric data. It is suitable for an analytical expression of wavefront, and one can obtain sufficient accuracy with a relatively small number of approximation coefficients. Properties of the proposed method are analyzed in this work. It is shown that the technique can be used for analyzing wavefront deformation in optical testing methods.     

Electronic structure and biological activity of nucleobases

HeI and HeII photoelectron spectra of 6-chloro-1,3-dimethyluracil have been measured. The assignment of the spectrum was made by comparison with photoelectron spectra of related compounds and by high-level OVGF calculations. The electronic structure changes in substituted nucleobases are discussed on the basis of photoelectron spectroscopic data. The electronic structure data are compared with structure-activity relationships regarding enzyme inhibition and complex formation. The electronic structure data give some insight into the nature of binding between nucleobases' derivatives and different enzymes whose activity they inhibit.