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111.
Maija Nissinen Terhi Alaviuhkola Kari Rissanen Jouni Pursiainen 《Journal of chemical crystallography》2006,36(12):863-868
The crystal structure of the potassium tris[3-(2-pyridyl)pyrazolyl]hydroborate has been determined. Potassium tris[3-(2-pyridyl)pyrazolyl]hydroborate crystallizes in the orthorhombic space group Pca21 with the parameters a=30.7323(5) ?, b=8.3083(1) ? and c=9.2173(2) ?, V=2353.48(7) ?3 with Z=4. The crystal structure reveals the formation of continuous chains where two bidentate arms of the hydroborate ligand are coordinated to one potassium and the third to another cation. The structures of numerous transition metal and actinide salts have been reported during the last decades but no alkali metal complexes were available. 相似文献
112.
Alexander Shivanyuk Kari Rissanen SteffiK. Krner DmitryM. Rudkevich Julius Rebek Jr. 《Helvetica chimica acta》2000,83(8):1778-1790
Resorcinarene‐based cavitands 1a – c fold into a deep open‐ended cavity by means of intramolecular hydrogen bonds in both apolar solutions and the solid state. The X‐ray crystal‐structure analysis of cavitand 1a features a seam of secondary amide C=O⋅⋅⋅H−N interactions that bridge adjacent rings and are held in place by intra‐annular hydrogen bonds. This results in a cavity of 9.2×7.0 Å dimensions. The arrangement of the amides in 1a – 1c is cycloenantiomeric, with clock‐ and counterclockwise orientation of the head‐to‐tail amide sequence. Interconversion rates of the two enantiomers are controlled by solvent polarity: the rate is slow on the NMR time‐scale in aromatic solvents and CDCl3, but fast in (D6)acetone. The 1H‐ and 13C‐NMR‐spectral analysis is in agreement with the crystallographic data. Chiral cavitand 1b with eight HN−C(O)−C*HMeEt ((+)‐(S)) groups on its upper rim exists as two cyclodiastereoisomers (in a ca. 3 : 1 ratio) in apolar solution. A `library' of 512 diastereoisomeric cavitands 1c is obtained as a mixture by using the corresponding racemic acid chloride. 相似文献
113.
114.
115.
Aromatic hydrocarbons can be selectively recognized by four endo-functionalized molecular tubes through C/N-H...π interactions in nonpolar media with binding constants up to 1580 L/mol. 相似文献
116.
117.
We give a generalization of the Stone–Weierstrass property for subalgebras of C (X), with X a completely regular Hausdorff space. In particular, we study in this paper some subalgebras of C0(X), with X a locally compact Hausdorff space, provided with weighted norm topology. By using the Stone–Weierstrass property, we then describe the ideal structure of these algebras. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
118.
119.
J. Kurpeta V. -V. Elomaa T. Eronen J. Hakala A. Jokinen P. Karvonen I. Moore H. Penttilä A. Płochocki S. Rahaman S. Rinta-Antila J. Rissanen J. Ronkainen A. Saastamoinen T. Sonoda W. Urban Ch. Weber J. Äystö 《The European Physical Journal A - Hadrons and Nuclei》2007,31(3):263-266
Exotic, neutron-rich 111Mo and 115Ru nuclei, produced in proton-induced fission of 238U target, were separated with the IGISOL mass separator. The separator was coupled to the JYFLTRAP Penning trap to select
the ions of a single, desired element out of the isobaric IGISOL beam. Monoisotopic samples of 115Ru and 111Mo ions were observed with a microchannel plate detector after the trap or were implanted on a catcher foil for gamma- and
beta-ray coincidence spectroscopy. In spite of short data taking time new gamma transitions were identified in the beta decay
of very neutron-rich 115Ru. 相似文献
120.
Rissanen K 《Angewandte Chemie (International ed. in English)》2005,44(24):3652-3654