Quantitative structure-property relationships for vapor pressures of polybrominated diphenyl ethers

Based on quantum chemical descriptors, by the use of partial least squares regression, quantitative structure-property relationship models for subcooled liquid vapor pressures (PL) of polybrominated diphenyl ether (PBDE) congeners were developed. The Q2cum value of the optimal model obtained is as high as 0.993, indicating a good predictive ability and robustness of the model. Although disagreements were observed between the predicted log PL values and log PL values of validation set, the model obtained can still be used for estimating PL of other PBDE congeners, considering the fact that accurate PL values for compounds with low volatility are extremely difficult to determine experimentally. Intermolecular dispersive interactions play a leading role in governing the values of PL, followed by electrostatic, dipole-dipole and dipole-induced dipole interactions. Intermolecular dispersive interactions also govern the values of enthalpies of vaporization.