The average value of this parameter for all ILs and DSILs is approx. 531.4 cm 3 mol -1 , and the calculated extreme values (530.7 cm 3 mol -1 for AB0.9 and 532.0 cm 3 mol -1 for AB0.1) differ from the average value by about 0.1%. It should be noted here that DSILs containing a higher molar proportion of MCPA anion (AB0.1-AB0.5) have positive excess molar volume (Vm E20 ) values than the average, while at higher xdic values Vm E20 values fall below zero. This relationship is shown in Fig. . Positive values of Vm E20 indicate the presence of non-additive physical contributions in the analyzed system, including non-specific interactions between mixture components that alter the molar volume, while negative values are associated with chemical or structural interactions (e.g., changes in coulombic interactions or hydrogen bonds between mixture components, changes in free volume or ion packing). Thus, it can be predicted that an increase in the molar proportion of the dicamba anion above 0.5 plausibly causes a significant change in the nature of the interactions in DSIL. These changes may affect the chemical environment of MCPA anions, which explains the observed deshielding of hydrogen atoms in NMR spectra.