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[en] The core level binding energies and valence band spectra of MnS, MnSe, and MnTe have been examined by X-ray photoelectron spectroscopy. The results demonstrate that the compounds are substantially more ionic in character than related transition metal compounds, and that the compounds lack significant metal-metal interactions, accounting for the nontypical nature of the compounds as transition metal chalcides
[en] Low-temperature nuclear orientation experiments on radioactive 56Mn ions implanted into insulating, antiferromagnetic crystals of MnCl2·4H2O and CoCl2·6H2O are reported. In MnCl2·4H2O, comparison of the γ-ray anisotropy of the 56Mn nuclei with that of 54Mn, doped into the sample during growth, showed that both the 56Mn and 54Mn spins felt a very similar hyperfine field. The site occupancy factor in a simple, two-site model was deduced to be 0.96-0.07+0.04. In CoCl2·6H2O, the average hyperfine field for the implanted 56Mn was significantly less than that for 54Mn and corresponded to f=0.53±0.10
[en] Exposure of the manganese pentacarbonyl halides [Mn(C0)5X](X = Cl,Br or I), to 60Co γ-rays at 77K gives an S = 1/2 centre having a g ca. 2 and a large hyperfine coupling to 55Mn and the halogen nuclei. The results are interpreted in terms of electron addition into a sigma* orbital involving mainly the metal dsub(z)2 and halide psub(z) orbitals. A second centre having two apparent g values in the g = 6 region is also formed for all the three complexes. These again exhibit hyperfine coupling to 55M and to the halogen nuclei. Various structures are considered, and it is concluded that the most reasonable are cations formed by loss of an electron and one or more carbonyl groups with unpairing of the remaining electrons to to give S = 5/2. (author)
[en] A method for the sorting of manganese ore in particulate form according to the manganese content of the particles including the steps of irradiating the ore with neutrons to induce the reaction Mn (n, Gamma) 56Mn; detecting the gamma rays emitted by the 56Mn; and using the information so obtained to sort paricles of relatively high manganese content from particles of relatively low manganese content is discussed
[en] The AMS facility at China Institute of Atomic Energy has been equipped with a ΔE-Q3D detection system for the measurements of 53Mn. While the sample material of MnO2 and the extraction ions of MnO− were used previously in AMS measurement of 53Mn with fairly good results, a method has recently been developed with the extraction of MnF− from ion source using MnF2 and MnO2 + PbF2 as sample materials. As a result, a sensitivity of 10−14 (53Mn/Mn) has been achieved. Compared with the original MnO−/MnO2 approach, the method of MnF− extraction, combined with ΔE-Q3D detection technique, demonstrated an improved sensitivity for AMS measurement of 53Mn.
[en] Complete text of publication follows. Complete text of publication follows. The crystal structures of the α and β allotropes of manganese, are among the most complicated found in nature, with the α-Mn unit cell containing 58 Mn atoms shared between four crystallographically inequivalent sites, and the β-Mn unit cell containing 20 Mn atoms shared between two sites. A comprehensive neutron diffraction study of the alloys, α-MnT where T = Al, Cr, V, Co and Fe, and β-MnT where T = Al, In, Sn, Co and Fe has been carried out in order to determine their impurity site occupancies and lattice expansion properties. In the case of the β-MnT alloys, we find that Al, In and Sn preferentially occupy the site II β-Mn sublattice, while Fe and Co prefer site I, confirming most of the previous studies. For the α-MnT alloys, we find that Al and V display a strong preference for the site I α-Mn sublattice, while Fe and Co occupy sites III and IV. No site preference is observed in dilute α-MnCr. Large ionic radii non-TM impurities produce significant lattice expansion; 0.9%/at% In, 0.8%/at% Sn and 0.05%/at% Al, while TM impurities leave the β-Mn lattice constant virtually unchanged; 0.009%/at% Co and 0.01%/at% Fe. The preferential occupancies of these impurities are discussed in terms of their effect on the magnetic ground states of these alloys. (author)
[en] The observation of a sudden increase in collective behavior along neutron-rich even-even chromium and iron isotopes toward N=40 triggered several studies in recent years. Within the shell-model this sudden increase can only be reproduced by choosing an expanded valence space which allows excitations beyond N=40 and into the g9/2 and d5/2 orbitals. Less attention has been spent on neighboring odd-mass manganese isotopes with Z=25, although they are able to provide complementary sensitivity to state-of-the-art (shell model) interactions. Within this talk we will present lifetimes of low-lying excited states in 59,61,63Mn, which were deduced from a recoil distance Doppler-shift measurement. These isotopes were produced in side reactions of an experiment whose central aim was the determination of level-lifetimes in 58,60,62Cr.