Application of electrostatic solvent models to the electronic spectrum of mesityl oxide

Abstract EN

MNDO method has been carried out to determine the most stable structure of the two conforms of mistily oxide.

The final optimized geometry of the stable conform was used as input data for CNDO / S-CI solvent models.

Four models depending on the effective virtual charge were used to study the effects of non-specific interactions between the mistily oxide (solute) and solvent on electronic spectrum of the studied molecule.

These models are Germer Model (GM), Tapia Model (TM), Modified Solvation Model (MSM) and Modified Tapia Model (MTM).

CNDO / S results showed that GM was not successful whereas TM has correctly predicted the blue shift on ¹(nπ*) state but it failed for π→ π* transition.

MSM & MTM gave good results for the effects of solvent on the electronic spectrum which indicate a blue shift for n→ π* and a red shift for π→ π* transitions when the polarity of the solvent increases, and these results are in excellent agreement with experimental data of solvent effects, but the results of MSM are more precise than that of MTM).

These results are also interpreted by the dipole moments values of the ground state (1so) and ¹(nπ*) and ¹(π π*) excited states.