NOTES
3878
from the exchange broadening of the dominant n.m.r. line in the NH-COOH proton system. Experimental methods and rate calculations have been fully described elsewhere3 and need not be repeated here. Values for relevant n.m.r. parameters were taken from the previous work3b and are listed in Table I, footnote b. Solute concentrations were in the range 0.01 to 0.2 M . The following salts, when present as single solutes in acetic acid, were found to give negligible (