| Popis: |
The two anthracenocryptands 3,12-octano-3,12-diaza-6,9,31,34-tetraoxa[14](9, 10)anthracenophane, C 30 H 40 N 2 O 4 (A 22 ), and 4,13-octano-4,13-diaza-7,10,33,36-tetraoxa[6](9,10)anthracenophane, C 32 H 44 N 2 O 4 (A 33 ), were designed to direct interactions between π-electrons and Ag + . In each complex displaying 1 :1 stoichiometry, Ag + is encapsulated in the cavity of the cryptand and coordinated to O and N atoms of the diaza-crown ether. In (A 22 )/Ag + , complex (I), Ag + lies at a Ag + -anthracene mean plane distance of 3.01A. Two conformations of the silver complex (IIA) and (IIB) are observed in the crystal lattice of (A 33 )/Ag + , with different distances (5.14 and 4.46 A) between Ag + and the anthracene plane. The fluorescence properties of the crystals reflect the difference in geometry between (A 22 )/Ag + and (A 33 )/Ag + . The fluorescence spectra were recorded at room temperature with a Hitachi-Perkin-Elmer MPF44 fluorimeter corrected for emission and excitation. The same single crystals were used both for X-ray structure determination and fluorescence emission studies. The fluorescence is collected in a direction at right angles to the beam of the exciting light |
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