The preparation of thermally labile compounds is a great temptation in chemistry which requires a careful selection of reaction media and reaction conditions. With a new scanning technique denoted here as Cluster Harvesting, a whole series of metal halide compounds is detected by differential thermal analysis (DTA) in fused silica tubes and structurally characterized by X-ray powder diffraction. Experiments of the reduction of tungsten hexahalides with elemental antimony and iron are presented. A cascade of six compounds is identified during the reduction with antimony, and five compounds or phases are monitored following the reduction with iron. The crystal structure of Fe2W2Cl10 is reported, and two other phases in the Fe-W-Cl system are discussed.

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Phenomenological studies of WCl6 reduction with transition metal powders M = Mn, Fe, and Co have been recently reported. These reactions involve a series of reductive intercalation steps of M atoms into layered tungsten chloride arrangements, followed by exsolution of MCl2. In the series M = Fe, the presence of divalent iron is evidenced for Fe(x)WCl6, FeW2Cl10, Fe2W2Cl10, and (Fe,W)Cl2 by Mössbauer spectroscopy. Magnetic properties are reported. Bonding characteristics between tungsten atoms in edge-sharing [W2Cl10](n-) bioctahedra reveal that a double bond can be addressed to FeW2Cl10. A similar situation appears for Fe2W2Cl10, due to the localized and thus nonbonding character of the two electrons in the δ orbitals of this compound.

Small and medium-sized animals can be exposed to fast neutrons from a 2S5U-converter. Studies using tissue-equivalent ionization chambers in combination with a neutron-insensitive 7-ray dosemeter show that the y-ray and thermal neutron contaminations in the animal exposure field are small, amounting to S?; and 0.77; respectively of the total kerma. Forty mice may be irradiated simultaneously at the same fast-neutron centre-line dose rate up to a maximum of 10 rad min". The neutron spectrum, determined by proton-recoil spectrometry, gives a mean neutron energy of 1.04 Mer. For the first-collision recoil protons a track-average LET, equal to 57 kev per pm has been calculated.

A procedure combining thermal analyses and XRD powder diffraction is used to scan and detect a series of new compounds in the Mn‐W‐Cl system. Four new ternary Mn‐W‐Cl compounds are formed in a progressive reaction of tungsten hexachloride (WCl6) with manganese powder, in which tungsten is gradually reduced from W6+ to W2+. Among several DSC signals, the new compounds MnxWCl6, MnW2Cl10, (Mn, W)1–xCl2, and MnW6Cl14 are detected and their crystal structures are assigned or identified by X‐ray diffraction techniques. Magnetic properties are reported for MnW2Cl10 and MnW6Cl14.