Please find as attachment an example of pair dipeptidic isomers. In general, these objects are very distinguishable both using solid-state Raman and IR as you can read in the shown ref. [1] as well as, where there has a set of
IR- and Raman spectra of amides of amino acids, di- and oligopeptides. Furthermore, the shown dipeptides are commercial products (Sigma-Aldrich), and thus, you may use them as models with high reproducibility of the data.