Question

Compare and contrast infrared and raman spectra with NMR techniques for their capability of characterizing 1) tacticity and

2) Cis and trans double bonds in polymers

Answer 1

1) With the gelp of IR specroscipy we can identify the functional groups of the compound and it also shows the different frequency values in Cis-Trans isomerisation.

2) 1HNMR helps the identification of type of protans present in the molecule, It shows the different values for cis-Trans isomers and also shows the different value for the stereoisomers (tacticity).

3) Raman specroscopy: It gives the orientation of the atoms in the molecule like Cis-trans isomers.

In the case of multiple polymorphic forms, it can also be used to identify the polymorphic form.

As with single molecules, a given solid material has characteristic phonon modes that can help an experimenter identify it.