Spectra high-resolution

These days, remarkably high-resolution spectra are obtained for positive and negative ions using coaxial-beam spectrometers and various microwave and IR absorption teclmiques as described earlier. Infonnation on molecular bond strengths, isomeric fonus and energetics may also be obtained from the teclmiques discussed earlier. The kinetics of cluster-ion fonuation, as studied in a selected-ion flow tube (SIFT) or by high-pressure... 

B1.12.4.5 HIGH-RESOLUTION SPECTRA FROM QUADRUPOLAR NUCLEI... 

Advantages. Compared to DOR, a small rotor can be used allowing relatively fast spiiming speeds high RF powers can be attained and if the coil is moved with the rotor a good filling factor can be obtained. In the isotropic dimension high-resolution spectra are produced and the second dimension retains the anisotropic information. 

Quack M and Stohner J 1993 Femtosecond quantum dynamics of functional groups under coherent infrared multiphoton excitation as derived from the analysis of high-resolution spectra J. Rhys. Chem. 97 12 574-90... 

Recent observations of fluorescence in NpF6 and PuF6 (46) are consistent with the energy-level scheme proposed. However, comparison of the calculated level structure with high-resolution spectra of PuFg (44) confirms that much of the observed structure is vibronic in character, built on electronic transitions that are forbidden by the inversion symmetry at the Pu site. 

Figure 2. The high resolution spectra of species 5 and 6 show N(ls) peaks at 401 eV (nonprotonated nitrogen) and 402.7 eV (protonated nitrogen) while samples neutralized with base, T, do not show protonated nitrogen peaks. Also, the latter sample shows two species...

The second and third energy terms in equation (1) could be interchanged without any effect (i.e. it is impossible to say which electron fills the initial core hole and which is ejected as an Auger electron they are indistinguishable. The existence of different electronic states within the final doubly ionized atom may furthermore lead to fine structure in high-resolution spectra. 

Abstract. In this contribution we present the results based on high-resolution spectra of 45 clump stars of the Galactic field. The main atmospheric parameters and abundances of 12C, 13C, N, O and other mixing sensitive chemical elements were investigated. Elemental ratios in the sample of field stars are compared to the results available for evolved stars in open clusters and to the theoretical prediction of extra mixing in stellar interiors. 

Abstract. In an effort to determine accurate stellar parameters and abundances for a large sample of nearby stars, we have performed the detailed analysis of 350 high-resolution spectra of FGK dwarfs and giants. This sample will be used to investigate behavior of chemical elements and kinematics in the thick and thin disks, in order to better constrain models of chemical and dynamical evolution of the Galaxy. 

The drawback of this kind of studies is that no reliable indicator of the O abundance is available moreover, informations on the Na abundances are difficult to obtain. However, thanks to the new generation of efficient spectrographs mounted at 8-10m class telescopes, high resolution spectra for unevolved stars in GCs are feasible. 

There have been more measurements of Li in stars than any other chemical element. The vast majority have been derived from high resolution spectra of the strong Lil6708A resonance doublet. Only a fraction of the observational material can be reviewed here. The reader is referred to some other reviews for a more complete picture [16,25]. 

Cr 261 is one of the oldest open clusters in the Galaxy, with an estimated age ranging from 7 to 11 Gyr ([5] [16] [4]). The metallicity, derived from both low-resolution and high-resolution spectra, is slightly subsolar ([Fe/H]=—0.2 ... 

In the central region of Sculptor we have high resolution spectra providing direct abundance measurements for numerous elements (Hill et al., in prep). In Fig. 3 we show the preliminary results for the a-elements (Ca, Mg Ti) compared with similar observations of stars in our Galaxy. It is clear that the overall distribution of [a/Fe] versus [Fe/H] in Scl does not match our Galaxy, except for a small number of the most metal poor stars in Scl which overlap with Galactic halo stars. 

In order to test the current evolution and nucleosynthesis models predicting the formation and the yields of such carbon stars, we have collected high-resolution spectra of stars located in the SMC and the Sagittarius dwarf galaxy, extragalactic systems with low average metallicity and well known distances. 

Thus, by the correct choice of experiment, it is possible to obtain high-resolution spectra from a wide variety of nuclei in the solid state and spectra of this type have many applications to inorganic chemistry. 

Building High-Resolution Spectra Using Projection-Reconstruction Techniques... 

As in the case of CPMAS, the CP-MQMAS transfers are incapable of enhancing the sensitivity, but can provide dipolar filtering of high-resolution spectra of quad-rupolar nuclei and, most importantly, serve as a method for obtaining the HETCOR... 

The following four vibrations may be observed in the high-resolution spectra of compounds containing both —CH2 and —CH3 groups. 

The XPS data were acquired on a Physical Electronics model 5400 XPS system using a Mg anode. For survey spectra, the pass energy was 44.75 eV with a step size of 0.5 eV. The time per step was 50 msec. High resolution spectra were acquired with a pass energy of 35.75 eV and step size of 0.1 eV, The time per step was 50 msec. Thermogravimetric data were obtained on a Perkin-Elmer, Diamond Thermogravimetric/ Differential Thermal Analyzer (TG/DTA) with Pyris software, version 7.0-0.0110. 

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