【Abstract】 The dimeric property of bis(2 - ethylhexyl) phosphoric acid(HDEHP) in different diluents has been studied. The experimental results show that the dimeric degree of HDEHP increases with the decrease of the polarity of diluents.This kind of effect has been discussed from the point of view of intermolecular interactions between the extractant molecules and the diluent ones. The dimeric constantswere related to the physical constants and experiencial parameters of the diluents.The following expression hasbeen obtained lg K2 =6 .4 5 9- 4 .4 6 4 (ε- 1) /(2 ε+ 1) - 1.96 5 (n D2 - 1) /(n D2 +1) - 3.199α- 5 .6 6β.更多还原