ISSN:
1572-8927
Keywords:
Sodium-23 NMR
;
chlorine-35 NMR
;
intrared
;
Raman
;
perchlorate ion
;
ion pairs
;
nonaqueous solvents
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Sodium perchlorate solutions in several nonaqueous solvents were examined by23Na,35Cl-NMR, infrared, and Raman spectroscopic techniques. The formation of contact ion pairs lowers the symmetry of ClO 4 − ion from Td to C3v or C2v provided that the interaction is fairly strong. This was manifested for NaClO4 solutions in acetonitrile, tetrahydrofuran, and pyridine. Combination of the vibrational measurements with NMR shows that in the above three cases the anion-cation interactions are quite strong. Sodium-23 NMR studies confirm the above results and, being a more sensitive technique, also indicates weak cation-anion interaction in propylene carbonate, formic acid, acetone, methanol, ethanol, dimethyl sulfoxide, and water. In all solvents the23Na resonance shifts upfield with increasing concentration of NaClO4, indicating that the replacement of solvent by ClO 4 − ion decreases electron density around the cation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00648223
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