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The effect of temperature (20-60 °C) on the fluorescence emission of (E)-N-(3-chlorophenyl)-2-(3,4,5-trimethoxybenzylideneamino)-4,5,6,7-tetrahydrobenzo [b]thiophene-3carboxamide (ENCTTTC) is studied in different solvents. It is found that there is no shift in the position of fluorescence maxima, but the intensity decreases with increasing temperature, which depends on the polarity of the solvent. A mechanism of fluorescence quenching with rise in temperature is discussed in terms of the relative location of lowest (ππ*) (nπ*) states and the energy difference between them. The change in temperature brings about a change in the probabilities of radiative and nonradiative transition. The nonradiative deactivation of excited states in the absence of a quencher is temperature dependent and its thermal activation energy has been determined. [ABSTRACT FROM AUTHOR]

We measured the spontaneous-emission branching ratios of 69 levels in Sm II selectively populated via single-frequency laser excitation of a 10 keV ion beam. The levels studied had term energies up to 29 600 cm–1, and decay branches with spontaneous emission in the range 250–850 nm were detected. The experimental accuracy was in the range of 10%. We used these branching ratios along with our previously determined radiative lifetimes to infer transition probabilities and oscillator strengths for 608 transitions in the wavelength range 363–771 nm, which are useful for stellar abundance determinations.PACS Nos.: 32.70.Cs, 95.30.Ky [ABSTRACT FROM AUTHOR]

Multicharged Xe ions following de-excitation of K-, L1-, L2,3-, M1-, M2,3-, and M4,5-subshell vacancies are calculated using a Monte-Carlo algorithm to simulate the vacancy cascade development. Fluorescence yield (radiative) and Auger and Coster–Kronig yields (nonradiative) are evaluated. The decay of the K hole state through radiative transitions is found to be more probable than through nonradiative transitions in the first step of de-excitation. On the other hand, the decay of L and M vacancies through nonradiative transitions are more probable. Ions, mainly produced from Xe in the K-shell vacancy state, are found to be Xe7+, Xe8+, Xe9+, and Xe10+. The charged Xe8+ ions predominate in the charge state distributions. The main product from the L1-shell ionization is found to be Xe8+ and Xe9+ ions, while the Xe8+ ions predominate at the L2,3 hole states. The charged Xe6+, Xe7+, and Xe8+ ions come mainly from 3s1/2 and 3p1/2,3/2 ionization, while Xe in 3d3/2,5/2 hole states becomes mainly Xe4+ and Xe5+ ions. The present results are found to agree well with the experimental data.PACS No.: 32.40.Hd [ABSTRACT FROM AUTHOR]