This experiment is a computational supplement to Part B of the tin chemistry described in "Synthesis and Technique in Inorganic Chemistry" (Exp 7; see below for the complete citation).* Students will optimize and compute IR spectra for the cis and trans and corresponding linkage isomers of tetrachlorbis(dimethylsulfoxide) tin(IV). A comparison of experimental (IR spectra) and computational data (enthalpies of formation; IR spectra) will aid them in determining the most likely product of this simple synthesis and in identifying the S-O vibrations in their experimental spectrum.
*G. S. Giorlami, T. B. Rauchfuss, R. J. Angelici “Synthesis and Technique in Inorganic Chemistry: A Laboratory Manual”, Third Edition
Computational software package.
Computational time is minimized in this experiment by using a semi-empirical method (PM3).Unfortunately this also means that the IR spectra are more qualitative than quantitative.However, given that four structures must be studied, this was deemed to be a reasonable compromise. Since this is a computational exercise, computer access during typical laboratory sessions is required.Since I run my lab in the round-robin style, this was not a significant issue (1-3 computers were needed in any given week).