Detection of Rb/sup -/ in crystalline rubidides by /sup 87/Rb nuclear magnetic resonance

Journal Article · Thu Jan 02 04:00:00 EST 1986 · J. Phys. Chem.; (United States)

DOI:https://doi.org/10.1021/j100273a006· OSTI ID:5827958

Tinkham, M L; Ellaboudy, A; Dye, J L; Smith, P B

The rubidide anion, Rb/sup -/, was detected in crystalline alkalides by /sup 87/Rb magic-angle-spinning (MAS) NMR spectroscopy. The compounds Rb/sup +/ (15-crown-5)/sub 2/Rb/sup -/, Cs/sup +/(15-crown-5)/sub 2/Rb/sup -/, and Cs/sup +/(18-crown-6)/sub 2/Rb/sup -/ were found to be pure rubidides with the same isotropic chemical shift of -186 +/- 2 ppm relative to Rb/sup +/(aq). The frequency dependence of the chemical shift and line width correspond to a quadrupole coupling constant of 1.2 +/- 0.2 MHz for Rb/sup -/. The systems RbK(15-crown-5)/sub 2/, RbK(18-crown-6), and Rb(18-crown-6) are mixtures. Samples of Rb/sub 2/(cryptand 2.2.2) and Rb/sub 2/(18-crown-6) that were expected to contain Rb/sup -/ showed no signal. Although the signal of Rb/sup +/ could be detected in the simple salts RbCl, RbI, and RbSCN, the complexed rubidium cation could not be detected in the solid state. Signals from both Rb/sup +/(15-crown-5)/sub 2/ (..delta.. nu/sub 1/2/ approx. = 5000 Hz) and Rb/sup -/ (..delta.. nu/sub 1/2/ = 150 Hz) were detected in solutions of Rb/sup +/(15-crown-5)/sub 2/Rb/sup -/ in dimethyl ether in the presence of excess 15-crown-5. This work represents the first observation of the NMR spectrum of Rb/sup -/ in solids and of complexed Rb/sup +/ in solution. 32 references, 3 figures, 1 table.

• Research Organization: Michigan State Univ., East Lansing
• OSTI ID: 5827958
• Journal Information: J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Journal Issue: 1 Vol. 90:1; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALCOHOLS
ALKALI METAL COMPOUNDS
ALKALI METAL ISOTOPES
ANIONS
AQUEOUS SOLUTIONS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CATIONS
CESIUM 133
CESIUM ISOTOPES
CHARGED PARTICLES
CHEMICAL ANALYSIS
CHEMICAL SHIFT
DATA
DISPERSIONS
EXPERIMENTAL DATA
FREQUENCY RANGE
GLYCOLS
HYDROXY COMPOUNDS
INFORMATION
INTERMEDIATE MASS NUCLEI
IONS
ISOTOPES
LINE WIDTHS
MAGNETIC RESONANCE
MHZ RANGE
MHZ RANGE 01-100
MHZ RANGE 100-1000
MIXTURES
NUCLEAR MAGNETIC RESONANCE
NUCLEI
NUMERICAL DATA
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC POLYMERS
POLYETHYLENE GLYCOLS
POLYMERS
RADIOISOTOPES
RESONANCE
RUBIDIUM 87
RUBIDIUM COMPOUNDS
RUBIDIUM ISOTOPES
SOLIDS
SOLUTIONS
STABLE ISOTOPES
YEARS LIVING RADIOISOTOPES