Relationship between molar refraction and n-octanol/water partition coefficient.

Area of Science:

• Environmental Chemistry
• Physical Chemistry

Background:

• The n-octanol/water partition coefficient (Pow) is crucial for assessing chemical behavior in the environment.
• Understanding factors influencing Pow is essential for predicting chemical fate and transport.

Purpose of the Study:

• To investigate the relationship between molar refraction and the n-octanol/water partition coefficient (Pow) for non-hydrogen bonding organic chemicals.
• To establish a predictive model for Pow based on molar refraction.

Main Methods:

• Analysis of observed Pow values and calculated molar refraction for various organic compounds.
• Focus on London's dispersion force as the primary contributor to van der Waals forces.

Main Results:

• Molar refraction was identified as the most significant factor determining Pow, correlating with London's dispersion force.
• The established relationship was validated using data from halogenated alkanes, alkenes, aromatics, and polycyclic aromatic hydrocarbons.

Conclusions:

• Molar refraction provides a reliable basis for estimating Pow for chemicals lacking hydrogen bonding capabilities.
• This method offers a practical alternative to laborious experimental Pow measurements for preliminary hazard assessments of new chemicals.