K. Adachi et al., MEASUREMENTS OF SELF-DIFFUSION COEFFICIENTS OF MONENSIN IN CHLOROFORMSOLUTION BY PFG-NMR, Journal of the Chemical Society. Faraday transactions, 93(18), 1997, pp. 3347-3350
Citations number
19
Categorie Soggetti
Chemistry Physical","Physics, Atomic, Molecular & Chemical
The self-diffusion coefficients D of MonH . H2O and MonNa have been me
asured by pulsed held gradient NMR (PFG-NMR) as a function of the conc
entration C. An exponential dependence of D on C has been found and ex
plained on the basis of the free volume theory. The diffusion coeffici
ents in the infinite dilute solution D()) for MonH . H2O and MonNa hav
e been estimated by extrapolating to C = 0 using the relationship betw
een diffusion coefficient and solute concentration based on free volum
e theory. Valves of D(0) estimated in this way have been applied to th
e Stokes-Einstein equation in order to obtain Stokes' radii. The radiu
s of MonNa (0.511 nm) was larger than that of MonH . H2O (0.484 nm). T
hese values were not very different from the radii of gyration (0.435
nm) in crystalline MonH . H2O.