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111.
The odd-mass nucleus 107Cd was investigated in the reactions . The constructed level scheme is based on results, obtained from singles γ-ray spectra and excitation functions, from the measurements of delayed γ-rays, of γ-γ coincidences, of internal conversion electrons and of γ-ray angular distributions. Two new isomers were observed. The first one, interpreted as the neutron state at 845.6 keV has a half-life of 67 ± 6 ns. This isomeric state is populated by a strong E2 cascade. Bands built on the other intrinsic states with spins and parities and are not strongly populated. For the second isomeric state at an excitation energy of 2679 keV a half-life of 55±4 ns was determined. This isomer is probably a three-quasiparticle state. Its configuration can be proposed as . 相似文献
112.
113.
The onset of Al 2p transitions of VAl3, FeAl, NiAl, NiAl3, CuAl2, PrAl2 and the disordered alloys VAl (16 at % Al, 28%, 41%), FeAl (11%) is shifted up to 1.1 eV. New pronounced structure develops close to the onset which for NiAl agrees with a density of states calculation by Connolly and Johnson. 相似文献
114.
115.
H. J. Jensen G. B. Hagemann P. O. Tjøm S. Frauendorf A. Atac M. Bergström A. Bracco A. Brockstedt H. Carlsson P. Ekström J. M. Espino B. Herskind F. Ingebretsen J. Jongman S. Leoni R. M. Lieder T. Lönnroth A. Maj B. Million A. Nordlund J. Nyberg M. Piiparinen H. Ryde M. Sugawara A. Virtanen 《Zeitschrift für Physik A Hadrons and Nuclei》1991,340(4):351-362
The strongly shape driving πh9/2[541]l/2? configuration with α=+1/2 exhibits some anomalous, and so far unexplained, features concerning the crossing frequency, ?ωc, the aligned angular momentum, ix, and interaction strength, at the alignment of the first pair of i13/2 quasineutrons in several odd-Z rare earth-nuclei. The h9/2[541]1/2? and h11/2[523]7/2? bands have been studied in the stably deformed rare-earth nucleus163Tm to investigate these features. A difference in band crossing frequency of ~ 80 keV between the two bands is found. Rotational bands built on these two configurations have been found to cross in the spin range I=25/2–29/2 ?. Theγ-decay pattern between the two bands is established in the crossing region and analysed in terms of a moderate shape difference between them. A theoretical estimate of the size of the interaction strength between the two bands is presented and compared to the experimental value. The observed band structure in163Tm is very similar to that of167Lu which has 2 protons and 2 neutrons in addition. This observation is discussed in relation to the similarity of the yrast bands of the two even-even “core” nuclei162Er and166Yb, for which theγ-transition energies are identical within ~0.2 keV below the vi13/2 crossing. 相似文献
116.
The unpaired particle in an odd-mass transitional nucleus exerts forces on the rest of the system leading to an effective shape which is in general dependent on thej-orbital occupied by the extra particle. To account for this polarization effect we propose to modify the collective matrix elements by a phenomenological polarization factor. This enables us to describe also such band structures by the core-particle coupling model for which the common coupling rules seem to fail. Selecting a typical case the model is applied to123I in order to demonstrate the important role of the polarization. The calculation reproduces fairly well all band structures including theirM1 andE2 decay properties. 相似文献
117.
Hans Hagemann Marcin Dulak TomaszA. Wesolowski Christian Chapuis Janusz Jurczak 《Helvetica chimica acta》2004,87(7):1748-1766
By means of 1H‐NOESY‐ and Raman‐spectroscopic analyses, we experimentally demonstrated the presence of the equatorial N? Me conformer of King's sultam 4b in solution, resulting from a rapid equilibrium. As a consequence, the value of the N lone‐pair anomeric stabilization should be revised to 1.5–1.6 kcal/mol. Independently from the N tilting, natural bond orbital (NBO)‐comparative analyses suggest that the S d* orbitals do not appear as primordial and stereospecific acceptors for the N lone pair. Second, the five‐membered‐ring sultams do not seem to be particularly well‐stabilized by the S? C σ* orbital in the N‐substituted pseudo‐axial conformation, as opposed to an idealized anti‐periplanar situation for the six‐membered‐ring analogues. In this latter case, the other anti‐periplanar C? C σ* and C(1′)? H/C(2′) σ*orbitals are as important, if not more, when compared to the S? C σ* participation. In the pseudo‐equatorial conformation, γ‐sultams particularly benefit from the N lone‐pair hyperconjugation with the anti‐periplanar S? O1 σ* and C(2)? H/C or C(1′)? H/C σ* orbitals. This is also the case for δ‐sultams when the steric requirement of the N‐substituent exceeds 1.6 kcal/mol. When both axial and equatorial conformations are sterically too exacting, the N‐atom is prone to sp2 hybridization or/and conformational changes (i.e., 12c ). In that case also, the mode of stereoelectronic stabilization differs from γ‐ to δ‐sultams. 相似文献
118.
A new member belonging to the binary phase diagram of BaF2 and BaCl2 was synthesized. The single domain crystals of Ba12F19Cl5 can be prepared from a nonstoichiometric flux with molar ratio of 1 : 1 between BaFCl and BaF2. The compound crystallizes at room temperature in the non-centrosymmetric hexagonal space group P6 2m with a = b = 1408.48(14) and c = 427.33(5) pm. Three different barium environements with coordination number of nine are found. The barium fluorine distances vary between 250.59(6) – a short distance compared to other Ba? F distances – and 302.7(1) pm and barium chlorine distances between 331.55(3) and 336.19(15) pm. This compound is further characterized using Raman spectroscopy. 相似文献
119.