Plutonium spectra

The spectra of both plutonium compounds have strong absorption bands at 3400 cm-1 and 1600 cm-1 that are interpreted as due to C-H and C=C stretching frequencies. The IR spectrum of has a... 

Plutonium(IV) polymer has been examined by infrared spectroscopy (26). One of the prominent features in the infrared spectrum of the polymer is an intense band in the OH stretching region at 3400 cm 1. Upon deuteration, this band shifts to 2400 cm 1. However, it could not be positively assigned to OH vibrations in the polymer due to absorption of water by the KBr pellet. In view of the broad band observed in this same region for I, it now seems likely that the bands observed previously for Pu(IV) polymer are actually due to OH in the polymer. Indeed, we have observed a similar shift in the sharp absorption of U(0H)2S0ir upon deuteration (28). This absorption shifts from 3500 cm 1 to 2600 cm 1. 

Stability and Electronic Spectrum of Cesium Plutonium Hexafluoride... 

Only two complex fluorides of pentavalent plutonium are known, both having been prepared by Penneman et al. ( 1). One of these, Rb2PuF7, appeared to be stable its crystal structure ( 1) and its electronic spectrum (2) have been reported. The other, CsPuF6, appeared to decompose after a few days (J ) and only its crystal structure was reported. Our interest in the bonding and electronic structure of Pu(V) and particularly in Pu(V) fluorides prompted the present study of CsPuFg. 

The plutonium-uranium fuel cycle has particular advantages in fast spectrum... 

Line III has a great interest, because it takes into account in the case of U partial localization effects of 5f states. Such partial localization effects, if present in uranium metal, should be even more visible in the emission of plutonium metal. For this reason, line III will be discussed after the analysis of the valence band spectrum of plutonium metal. 

The starting Hamiltonian H has been also used to make a link between ab-initio LMTO band structure calculation and a DMFT treatment of correlations for the studies of LaTiOs [9] and Plutonium [10]. This last approach, assuming infinite dimension, goes beyond our approach. We only expect to be able to describe the coherent part of the spectrum, whereas the incoherent part leading to lower and upper Hubbard subbands are not accessible in our model, however as already stressed, variationally based. 

The chlorocomplex salt, Cs3fAm02Cl4], is isostructural with the analogous neptunium(V) and plutonium(V) compounds.206 Its vibrational spectrum has also been reported.185... 

Absorption Spectra, of Aqueous Ions. The absorption spectra of Pu(III) [22541-70-4], Pu(IV) [22541-44-2], Pu(V) [22541-69-1], and Pu(VI) [22541-41-9] in mineral acids, ie, HC104 and HN03, have been measured (78—81). The Pu(VII) [39611-88-61] spectrum, which can be measured only in strong alkali hydroxide solution, also has been reported (82). As for rare-earth ion spectra, the spectra of plutonium ions exhibit sharp lines, but have larger extinction coefficients than those of most lanthanide ions (see Lanthanides). The visible spectra in dilute acid solution are shown in Figure 4 and the spectrum of Pu(VII) in base is shown in Figure 5. The spectra of ions of plutonium have been interpreted in relation to all of the ions of the 5f elements (83). 

Figure 13.3 Alpha spectrum of oxidised and reduced plutonium species as separated by the neodymium fluoride technique (oxidised yield tracer 236Pu, reduced yield tracer 242Pu).

Isotope Effects in the Molecular Spectrum of Plutonium Hexafluoride, R. Kugel, C. Williams, M. Fred, J.G. Malm, W.T. Camall, J.C. Hindman, W.J. Childs, andL.S. Goodman, J. Chem. Phys. 65, 3486-3492 (1976). 

Figure 15.2 Alpha particle spectrum for a purified plutonium sample.

The spectra of both plutonium compounds have strong absorption bands at 3400 cm and 1600 cm that are interpreted as due to C-H and C=C stretching frequencies. The IR spectrum of C2H l2 has a broad complex absorption from 2800-4000 cm and a sharp, strong band at 1128 cm . Absorption in the 3000 cm region is normally associated with CH stretching vibrations.( ) The normal CH2 stretch is found at higher frequencies in C=CH2 and CsCH groupings. 

Plutonium(IV) polymer has been examined by infrared spectroscopy (26). One of the prominent features in the infrared spectrum of the polymer is an intense band in the OH stretching region at... 

Finally, the highest valence state reported for plutonium in a non-oxygen-containing compound is exemplified in PuFe whose optical spectrum has been shown to be extremely complex (39). Estimated free-ion. Table V, and ligand-field parameters used in the present analysis are consistent with those reported earlier (44), but differ considerably from the free-ion parameters developed by Boring and Hecht (45) whose values for F and F would appear to us to be distorted. The crystal-field parameters characteristic of NpFe, Table VII, should represent a good basis for estimating the similar interaction in PuFe Our results are summarized in Fig. 10. 

Plutonium. The most fully known actinide spectrum is that of neutral plutonium and is represented in Figure 7 as an example (6). Each... 

Figure 1. Absorption spectra of plutonium(III). (1) Pu(III) in IM HCIO (2) the PuCIq ion in 85% succinonitrile-15% acetonitrile. This solution was prepared by dissolving PuClg in the solvent saturated with (C2Hg) NCl and containing a small amount of anhydrous HCl. The PuCIq spectrum was corrected for 2.0% Pu(IV) (as PuCIq ) which appears to constitute a slight overcorrection, and because of this the fine structure in the 670-870 mix region may not be exactly correct for PuCl/ ...

Amine Extraction. Extraction of uranium (VI) and plutonium (VI) from acetic acid with tri-iso-octylamine in xylene has been studied previously by Moore (JJ), who suggests that the extracted species is the triacetate ion. The spectra in Figure 1 show this is not the predominate species extracted into TOA-xylene solutions (9). Comparing the spectrum of this extracted uranium with the spectra of pure tetraacetate and triacetate complexes in Figure 3 shows that the TOA-xylene extracts a mixture of these ions that is largely tetraacetate uranyl complex. 

An example of this situation are plutonium isotopes, Pu and Pu. They are used for estimation of a burn up of nuclear fuel. As the energy difference of these alpha emitters is only 10 keV, the alpha particle spectrum is observed as an overlapped single peak. However, when a Si detector is used, which has an energy resolution of less than 10 keV (FWHM), the overlapped peaks can be analyzed by the least squares fitting technique. 

The UV-VIS spectrum of [Np02(Ll)] complex contains absorption band at 977 nm that is considered as evidence of Np(V) presence and indication of the change in the coordination sphere of Np atom in solution. Isoamethyrin LI also forms plutonyl complex [Pu02(Ll)], when treated with acidic solution of plutonyl(VI) chloride. Taking into account that Pu is reduced more readily than Np, authors made the conclusion about pentavalent state of plutonium that is supported by the absence of Pu(Vl) absorption peak near 830 nm. The similar changes in the spectra of L2-L5 with the addition of neptunyl or plutonyl are observed. By this means, the formation of Np(V) and Pu(V) complexes with... 

On the other hand, if the excited state is strongly localized, i.e. if the electron stays during the emission process on the same atom with the same spin, a resonance line can be emitted. The existence of an exciton-type state could be taken into consideration to explain the presence of the resonance lines but, except for thorium, the ratio of Mjy and My R line intensities is different from the ratio of the corresponding absorption line heights. In particular, the Mjy R line is absent in the spectrum of plutonium. As a consequence, the emission spectra cannot be interpreted suitably by ex-citonic transitions. 

S f distribution ofS-Pu. The plutonium 3d photoabsorption has been analyzed for modifications in the 5/excited states between the a and 5 phases (27, 35). The same sample is maintained at 400 °C during the analysis to give the 5 phase spectrum and at room temperature for the a phase. The variation of the photoabsorption coefficient with photon energy near the My ionization limit is plotted in Fig. 7. A very marked modification in the My photoabsorption according to the temperature is observed. 

Lastly, it is known that the relaxation processes decrease considerably with increase in temperature. This could help to explain the difference between a and 6-plutonium. A resonance line should be expected in the My emission spectrum of 6 —Pu. Its observation is experimentally difficult and shall be attempted in the near future. 

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