Extended analysis of Xe VII and Xe VIII

A pulsed discharge light source to study the six and seven times ionized xenon spectra in the 419–4642 Å region was used. A set of 40 transitions of Xe VII and 25 transitions of Xe VIII were classified for the first time. We revised the values for the previously known energy levels and extended the analysis for Xe VII to 10 new energy levels belonging to 5s6d, 5s7s and 5s7p, 4d95s25p even and odd configurations, respectively. Seven new energy levels of the core excited configuration 4d95s5d of Xe VIII are presented. For the prediction of the atomic parameters, energy levels, and transition, relativistic Hartree–Fock calculations were used.

Metastable level properties of the excited configuration 4p64d84f

Metastable levels in rhodium-like ions with the ground configuration 4p64d9 and the excited configurations 4p64d84f and 4p54d10 are investigated. The ab initio calculations of the level energies, radiative multipole transition probabilities are performed in a quasirelativistic Hartree–Fock approximation employing an extensive configuration interaction based on quasirelativistic transformed radial orbitals. Systematic trends in the behavior of calculated radiative lifetimes of the metastable levels are studied for the ions from Z = 60 to Z = 92. The significance of the radiative transitions of higher multipole order (M2 and E3) for the calculated radiative lifetimes is demonstrated and discussed.

Theoretical Study on Fluorescence Spectra of Three Coumarin Derivatives

The fluorescence spectra of three coumarin derivatives are studied. Geometric configurations of the three compounds are optimized by DFT method of quantum chemistry on B3LYP/6-31G. There is no imaginary frequency in vibrational analysis. Their excitation spectra are calculated by TD-DFT method. Furthermore, geometric configurations in excited state of the three compounds are optimized by CIS method. Based on the excited configuration emission spectra are also calculated. All the calculated results are in good agreement with experimental values.

MODELING OF ALKYL SALICYLATE COMPOUNDS AS UV ABSORBER BASED ON ELECTRONIC TRANSITION BY USING SEMIEMPIRICAL QUANTUM MECHANICS ZINDO/s CALCULATION

Modeling of several alkyl salicylates based on electronic transition by using semiempriical mechanical quantum ZINDO/s calculation has been done. Object of these research were assumed only alkyl salicylates of C4 (butyl) until C8 (octyl) homologue with 4-7 example structures of each homologue. All of the computation have been performed using quantum chemistry - package software Hyperchem 6.0. The research covered about drawing each of the structure, geometry optimization using semiempirical AM1 algorithm and followed with single point calculation using semiempirical ZINDO/s technique. ZINDO/s calculations used a defined criteria that is singly excited - Configuration Interaction (CI), gap of HOMO-LUMO energy transition was 2 and degeneracy level was 3. Analysis of the theoretical spectra was focused in the UV-B (290-320 nm) and UV-C (200-290 nm) area. The result showed that modeling of the compound can be used for predicting the type of UV protection activity depending with the electronic transition in the UV area. Modification of the alkyl homologue relatively did not change the value of wavelength absorbtion to indicate the UV protection activity. Alkyl salicylate compounds were predicted as UV-C sunscreen or relatively the compounds have protection effect for UV-C. Keywords: alkyl salicylate, sunscreen, semiempirical methods