Wich level of theory should I use for an optimization on thioalkyne molecules?

01 January 1970 1 8K Report

I would like to fine a proper level of theory for chemical systems composed of thioalkyne moiety. My strategy is to perform several optimization and frequency calculations with different level of theory e.g. PBE, B3LYP, LDA, M06... Then I could compare the experimental IR spectrum with the predicted ones. Wich level of theory should I try and do you have other strategies in mind that could help me to accomplish my goal?

I have putted the structures of the molecules on wich I would like to perform the calculations in an attached fil.

Thank you.

Bojidarka B. Ivanova

Mr. Morency,

PBE.

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