Rubidium dimer , reaction

In solution, all 2,3,4,5-tetraethylstibolide anions 11b are chemically and magnetically equivalent, whereas in the solid state this is only the case for the rubidium and cesium derivatives and the dimeric TMEDA adduct of sodium 2,3,4,5-tetraethylarsolide 11a (M = Na). Exchange and dissociation reactions lead to a magnetic equivalence on the NMR timescale, which can be expected for mainly ionic compounds (Table 5) <20040M3417>. 

The other alkali metals have been less extensively studied. The propagation rates of polystyrylsodium, -potassium, -rubidium and -cesium have been measured in benzene and cyclohexane [72, 73]. The sodium compound still shows half order kinetics in active centre concentration and is presumably associated to dimers. The rates for the rubidium and cesium compounds are directly proportional to the concentrations of the active chains which are presumably unassociated in solution. Absolute kp values can be determined from the propagation rate in this case. Poly-styrylpotassium shows intermediate behaviour (Fig. 11), the reaction order being close to unity at a concentration of the potassium compound near 5 x 10 M and close to one half at concentrations around 10" M. It could be shown by viscosity measurements that association was absent in the low concentration range. In this system both K2 and kp can be measured. The results are summarized in Table 2. The half order reactions show a large increase in kpK between lithium and potassium which... 

Andrews and co-workers have used the matrix reaction between lithium atoms and some inorganic compounds to produce species of spectroscopic interest. Reaction of lithium with molecular oxygen [301] produces, in addition to the molecule Li02, the molecule LiO and a dimer Li2 02. Reaction with nitric oxide produced a nitroxide compound [302], but analysis of the infrared spectrum indicated that in this compound the lithium atom was bound to the oxygen atom (LiON), rather than to the nitrogen atom (LiNO), as would be expected by analogy with the known compounds HNO and RNO. The matrix deposition of lithium and nitrous oxide [303] leads to the formation of LiO and LijO. The other alkali metals have also been reacted in the same way with nitrous oxide [304]. Potassium, rubidium and caesium all led to the formation of the compounds MO and M2O. No sodium oxides were produced when sodium and nitrous oxide were co-deposited. This is to be compared with the mechanism advanced for the sodium-catalysed gas-phase reaction between N2O and CO, where sodium is assumed to react with N2O, (Section 4, ref. 

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