Cs3UP2S8, a Coordination Polymer Containing the Unprecedented [U=S]2+ Sulfidouranium(2+) Moiety

Although terminal chalcogeno ligands are well known for the group 5 and 6 transition metals, they are highly unusual for the oxophilic group 4 metals and unknown so far for the lanthanides or actinides. Cs₃UP₂S₈, is the first actinide compound containing a terminal M=S group. It was synthesized by reacting uranium metal, Cs₂S, S, and P₂S₅ in a 4:1:8:3 ratio at 700 °C in an eutectic LiCl/CsCl mixture. The crystal structure was determined by single‐crystal X‐ray diffraction techniques. Cs₃UP₂S₈ crystallizes in the rhombohedral space group R$\bar{3}$ [a = 15.5217(8) Å; c = 35.132(2) Å, V = 8305.0(8) ų, Z = 18]. The crystal structure is based on a tetrahedral network type, wherein the uranium atoms are coordinated by a unusual sulfido moiety and thiophosphate groups in a pseudo‐tetrahedral fashion. The U=S distance of 2.635(3) Å observed in the sulfide moiety is approx. 0.2 Å shorter than the average U–S single bond length, indicating a double‐bond type character.     

Silver as a capturing material for iodine released from lead–bismuth eutectic in various conditions

Journal of Radioanalytical and Nuclear Chemistry - The usage of silver as a filtering material for removal of iodine from the gas phase of a lead–bismuth eutectic based nuclear reactor was...     

Measurement of the electric form factor of the neutron at Q2 = 0.3-0.8 (GeV/ c) 2 ⋆

The electric form factor of the neutron, G_E,n, has been measured at the Mainz Microtron by recoil polarimetry in the quasielastic D(¯e, e¯n)p reaction. Three data points have been extracted at squared four-momentum transfers Q ² = 0.3, 0.6 and 0.8 (GeV/c)². Corrections for nuclear binding effects have been applied.This revised version was published online in March 2005. In the previous version, the email address of one author was inadvertently assigned to multiple authors.     

Measurement of RLT and ATL in the 4He(e, e’p)3H reaction at pmiss of 130-300 MeV/ c

We have measured the ⁴He(e, ep)³H reaction at missing momenta of 130-300 MeV/c using the three-spectrometer facility at the Mainz microtron MAMI. Data were taken in perpendicular kinematics to allow us to determine the response function R_LT and the asymmetry term A_TL. The data are compared to both relativistic and non-relativistic calculations.     

(Im-)possible ISOL beams

Refractory elements, i.e. elements with very high melting point and low vapor pressure, cannot be released in atomic form from an ISOL target. Therefore most of these elements are presently not available as ISOL beams. However, when reactive gases are introduced into the target, they may form volatile compounds with the refractory elements, allowing for an easier transport to the ion source. Particularly useful are high-temperature stable fluorides and oxides. By these chemical evaporation methods so far ISOL beams of the refractory elements C, Zr, Hf and Ta have been produced. We discuss how ISOL beams of B, Ti, Nb, Mo, Tc, Ru, W, Re, Os and Ir could be produced in a similar way.     

Thermochromatographic behavior of iodine in 316L stainless steel columns when evaporated from lead–bismuth eutectic

Journal of Radioanalytical and Nuclear Chemistry - Iodine evaporated from lead–bismuth eutectic (LBE) has been examined with respect to its adsorption behavior on stainless steel in various...