ISSN:
1572-8927
Schlagwort(e):
18-crown-6-ether
;
dibenzo-18-crown-6-ether
;
apparent molar volume
;
partial molar volume change on complex formation
;
methanol
;
acetonitrile
;
dimethylsulfoxide
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Chemie und Pharmazie
Notizen:
Abstract The apparent molar volumes of equimolar concentrations of 18-crown-6-ether (CE) or dibenzo-18-crown-6-ether (B2CE) and MCl (M=Na, K, or Cs) or MI in dilute solutions of anhydrous methanol, acetonitrile and dimethylsulfoxide have been calculated from density data measured at 25°C. After extrapolation to infinite dilution these results together with the apparent molar volumes of the crown ethers and the alkali metal halides were used to calculate the limiting partial molar volume change for the formation of the complexes. By noting that the charge of the complexed cation has been shown to be completely shielded from the solvent, the volume of complexation can be assumed to be a good estimation of the volume change due to electrostriction of the solvent by the cationic charge. The results are compared to the predictions of the Hepler equation.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00663999
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