High-spin states in 139 Pm are investigated via the 116 Cd( 27 Al, 4n) 139 Pm fusion-evaporation reaction at a beam energy of 120 MeV. The previously reported level scheme has been modified because of identifications of some linking and doublet transitions. The revised yrast πh 11/2 band obviously undergoes πh 11/2 → π (h 11/2 ) 3 → π (h 11/2 ) 3 ⊗ν(h 11/2 ) −2 band crossings athω = 0.45 and 0.39 MeV. Two negative-parity dipole bands have been assigned as πh 11/2 ⊗ν(h 11/2 ) −2 and πh 11/2 ⊗ν(h 11/2 ) −4 configurations, respectively, and can be considered as examples of magnetic rotational bands.

The Brønsted acidity of isomorphously substituted ZSM-5 by B, Al, Ga, and Fe has been studied at the B3LYP level of density functional theory. On the basis of the calculated proton affinity, natural charge on the acidic proton, and the adsorption energy of NH3, the Brønsted acidity increases in the order:  B−(OH)−Si < Fe−(OH)−Si < Ga−(OH)−Si < Al−(OH)−Si, in agreement with the experiment. In both Al and Ga modified clusters, the adsorbed NH3 becomes ammonium (NH4 +) stabilized by two N−H···O hydrogen bonds, while the physisorbed NH3 is stabilized by one N···H−O hydrogen bond in Fe and B substituted clusters. It is also found that NH3 adsorption changes the B coordination sphere.

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