Dipole moment and self-association of acesulfame and saccharin in 1,4-dioxane solution at 298.15 K

The density, refractive index, and electrical permittivity of 1,4-dioxane solutions of acesulfame [6-methyl-1,2,3-oxathiazine-4(3H)-one-2,2-dioxide] and saccharin [1,2-benzisothiazole-3(2H)-one-1,1-dioxide] were measured at 298.15 K. From the experimental data the limiting apparent specific volume, refraction, and polarization of acesulfame and saccharin were calculated. The electrical dipole moments of acesulfame and saccharin were estimated according to the Debye, Onsager, and Kirkwood approaches. The association via dipole-dipole interactions of acesulfame and saccharin was treated with the assumption that the dipole moment of dimeric species of acesulfame and saccharin is zero. The dimerization constants and dipole moments of corresponding monomeric species were evaluated. Since the fraction of monomers is close to unity it is worth mentioning that the dimerization effect is rather weak.