Synthesis and properties of neptunium(VI,V) and plutonium(VI) pertechnetates

Федосеев, А. М.; Budantseva, N. A.; Grigoriev, Mikhail S.; Guerman, K. E.; Krupa, J.C.

doi:10.1524/ract.91.3.147.19976

Cited by 37 publications

(33 citation statements)

References 4 publications

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“…The 11 Be source was collected in September 2001 at the ISOLDE facility at CERN. The 11 Be atoms were produced by proton bombardement in a Ta target, ionized by laser ionization [27], accelerated and transported to the measuring station where the ion beam passed two sets of collimators before being implanted into a Be foil (Goodfellow, LS226536 L C, thickness 0.01mm, purity 99.8+%). The average intensity of the collected beam was 3.6 · 10 6 ions/s, the collection took place for close to 40 hours.…”

Section: The Set-up and Source Productionmentioning

confidence: 99%

See 1 more Smart Citation

Rare βp decays in light nuclei

Borge¹,

Fraile²,

Fynbo³

et al. 2013

J. Phys. G: Nucl. Part. Phys.

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Beta-delayed proton emission may occur at very low rates in the decays of the light nuclei 11 Be and 8 B. This paper explores the potential physical significance of such decays, estimates their rates and reports on first attempts to detect them: an experiment at ISOLDE/CERN gives a branching ratio for 11 Be of (2.5 ± 2.5) · 10 −6 and an experiment at JYFL a 95% confidence upper limit of 2.6 · 10 −5 for 8 B.

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Section: The Set-up and Source Productionmentioning

confidence: 99%

“…The distance from the first collimator to the collection point was 177 mm. The transmission was optimized with a stable 23 Na beam and a radioactive 27 Mg beam, the fraction of the activity that deposited on the collimator was at most 12%.…”

Section: The Set-up and Source Productionmentioning

confidence: 99%

Rare βp decays in light nuclei

Borge¹,

Fraile²,

Fynbo³

et al. 2013

J. Phys. G: Nucl. Part. Phys.

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“…However, while most of the known alkali suppression tools were used to equip the ISOLDE ThO-184 thorium oxide target (neutron converter [2], 40 mm long and 60µm wall thickness RILIS radiation cooled niobium-cavity and drift field system), its drift-field reduction factor was close to unity. This shows that the contribution of the target material to the work function cannot be neglected.…”

Section: Figure 3 -Ratio Of the Activities Collected Under Opposite Dmentioning

confidence: 99%

“…The ISOLDE RILIS [2] produces close to 50% of the ISOLDE Radioactive Ion Beams (RIBs), of 14 elements. The RILIS operate at 10 to 11 kHz, the lasers beams are sent coaxially into a cylindrical high temperature metallic cavity.…”

Section: Time Structure Of the Laser Ionized Ion-bunchesmentioning

confidence: 99%

Alkali suppression within laser ion-source cavities and time structure of the laser ionized ion-bunches

Lettry

Catherall

Köster

et al. 2003

Nuclear Instruments and Methods in Physics Research Section B:

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The chemical selectivity of the target and ion-source production system is an asset for Radioactive IonBeam (RIB) facilities equipped with mass separators. Ionization via laser induced multiple resonant steps Ionization has such selectivity. However, the selectivity of the ISOLDE Resonant Ionization Laser Ion-Source (RILIS), where ionization takes place within high temperature refractory metal cavities, suffers from unwanted surface ionization of low ionization potential alkalis.In order to reduce this type of isobaric contaminant, surface ionization within the target vessel was used. On-line measurements of the efficiency of this method is reported, suppression factors of alkalis up to an order of magnitude were measured as a function of their ionization potential.The time distribution of the ion bunches produced with the RILIS was measured for a variety of elements and high temperature cavity materials. While all ions are produced within a few nanoseconds, the ion bunch sometimes spreads over more than 100 µs. This demonstrates that ions are confined within high temperature metallic cavities. It is the internal electrical field of these cavities that causes the ions to drifts to the extraction region and defines the dwell time of the ions in the cavity.Beam optics calculations were carried out to simulate the pulse shape of a RILIS ion bunch and are compared to the actual measurements. AbstractThe chemical selectivity of the target and ion-source production system is an asset for Radioactive Ion-Beam (RIB) facilities equipped with mass separators. Ionization via laser induced multiple resonant steps Ionization has such selectivity. However, the selectivity of the ISOLDE Resonant Ionization Laser Ion-Source (RILIS), where ionization takes place within high temperature refractory metal cavities, suffers from unwanted surface ionization of low ionization potential alkalis.In order to reduce this type of isobaric contaminant, surface ionization within the target vessel was used. On-line measurements of the efficiency of this method is reported, suppression factors of alkalis up to an order of magnitude were measured as a function of their ionization potential.The time distribution of the ion bunches produced with the RILIS was measured for a variety of elements and high temperature cavity materials. While all ions are produced within a few nanoseconds, the ion bunch sometimes spreads over more than 100 µs. This demonstrates that ions are confined within high temperature metallic cavities. It is the internal electrical field of these cavities that causes the ions to drifts to the extraction region and defines the dwell time of the ions in the cavity.Beam optics calculations were carried out to simulate the pulse shape of a RILIS ion bunch and are compared to the actual measurements.

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“…[ReO 4 ] À is known to bind to transition elements and lanthanides (Chakravorti, 1990), but there are few crystal structures of [ReO 4 ] À and [TcO 4 ] À binding to actinides, although there is spectroscopic evidence for their existence (Bol'shakov et al, 1967). Recently, we reported the isostructural crystal structures of [UO 2 (ReO 4 ) 2 (TPPO) 3 ] and [UO 2 (TcO 4 ) 2 (TPPO) 3 ] (TPPO = triphenylphosphine oxide), in which ReO À 4 and TcO À 4 are bound to U(VI) (John et al, 2004;Sarsfield et al, 2004) and the neptunyl(VI) pertechnetate complex [(NpO 2 ) 2 (TcO 4 ) 2 Á3H 2 O)] has also been reported (Fedosseev et al, 2003). Here we describe the structural characterization of model complexes of pertechnetate coordinating to tetravalent actinides, namely, [U(ReO 4 ) 4 (TBPO) 4 ] (I), [Th(ReO 4 ) 4 (TBPO) 4 ] (II) and [Th(TcO 4 ) 4 (TBPO) 4 ] (III) (TBPO = tri-n-butylphosphine oxide)], which may be related to the extracted species formed in solution during the PUREX process; compound (III) is the first example of a tetravalent actinide coordinated to pertechnetate.…”

Section: Introductionmentioning

confidence: 99%

Temperature-resolved study of three [M(M′O₄)₄(TBPO)₄] complexes (MM′ = URe, ThRe, ThTc)

Helliwell

Collison

John

et al. 2006

Acta Crystallogr Sect B

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The crystal structures of the title complexes were measured at several temperatures between room temperature and 100 K. Each sample shows reversible crystal-to-crystal phase transitions as the temperature is varied. The behaviour of [U(ReO4)4(TBPO)4] (I) and [Th(ReO4)4(TBPO)4] (II) (TBPO = tri-n-butylphosphine oxide) is very similar; at room temperature, crystals of (I) and (II) are isostructural, with space group I42m, and reducing the temperature to 100 K causes a lowering of the space-group symmetry to C-centred cells, space groups Cc for (I) and Cmc2(1) for (II). The variation of lattice symmetry of [Th(TcO4)4(TBPO)4] (III) was found to be somewhat different, with the body-centred cubic space group, I43m, occurring at 293 K, a reduction of symmetry at 230 K to the C-centred orthorhombic space group, Cmc2(1), and a further transition to the primitive orthorhombic space group, Pbc2(1), below 215 K. Elucidation of the correct space-group symmetry and the subsequent refinement was complicated in some cases by the twinning by pseudo-merohedry that arises from the lowering of the space-group symmetry, occurring as the temperature is reduced. All three of the crystal structures determined at room temperature have high atomic displacement parameters, particularly of the (n)Bu groups, and (III) shows disorder of some of the O atoms. The structures in the space group Cmc2(1), show some disorder of nBu groups, but are otherwise reasonably well ordered; the structures of (I) in Cc and (III) in Pbc2(1) are ordered, even to the ends of the alkyl chains. Inter-comparison of the structures measured below 293 K, using the program OFIT from the SHELXTL package, showed that generally, they are remarkably alike, with weighted r.m.s. deviations of the M, M' and P atoms of less than 0.1 A, as are the 293 K structures of (I) and (II) with their low-temperature counterparts. However, the structure of (III) measured in the space group Cmc2(1) is significantly different from both the structure of (III) at 293 K and that found below 215 K, with weighted r.m.s. deviations of the Th, Tc and P atoms of 0.40 and 0.37 A, respectively. An extensive network of weak intra- and intermolecular C-H...O hydrogen bonds found between the atoms of the nBu and [M'O4] groups probably influences the packing and the overall geometry of the molecules.

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Synthesis and properties of neptunium(VI,V) and plutonium(VI) pertechnetates

Abstract: Preparation, crystal structure and properties revealed through IR and visible absorption spectroscopy study of Np(V,VI), Pu(VI) compounds formed with pertechnetate anions are reported. Spectrophotometric study of Np(V) and Pu(VI) in NH

Cited by 37 publications

References 4 publications

Rare βp decays in light nuclei

Rare βp decays in light nuclei

Alkali suppression within laser ion-source cavities and time structure of the laser ionized ion-bunches

Temperature-resolved study of three [M(M′O₄)₄(TBPO)₄] complexes (MM′ = URe, ThRe, ThTc)

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Synthesis and properties of neptunium(VI,V) and plutonium(VI) pertechnetates

Abstract: Preparation, crystal structure and properties revealed through IR and visible absorption spectroscopy study of Np(V,VI), Pu(VI) compounds formed with pertechnetate anions are reported. Spectrophotometric study of Np(V) and Pu(VI) in NH

Cited by 37 publications

References 4 publications

Rare βp decays in light nuclei

Rare βp decays in light nuclei

Alkali suppression within laser ion-source cavities and time structure of the laser ionized ion-bunches

Temperature-resolved study of three [M(M′O4)4(TBPO)4] complexes (MM′ = URe, ThRe, ThTc)

Contact Info

Product

Resources

About

Temperature-resolved study of three [M(M′O₄)₄(TBPO)₄] complexes (MM′ = URe, ThRe, ThTc)