3. (10 points) Conjugated ladder polymers are a unique class of organic materials with properties such as large persistence length, zero conformational disorder, efficient intrachain electron delocalization, and excellent thermal/photochemical stability. A well-known conjugated ladder polymer called BBL has been used as an efficient electron-conducting material in various organic electronic devices (e.g. n-channel organic field-effect transistors, organic solar cells, organic thermoelectrics, etc). BBL is synthesized via condensation polymerization resulting in two isomers as shown below. Each isomer is equally likely to be formed during the polymerization reaction. BBL (isomer 1) BBL (isomer 2) (a) Visualize the distribution of isomer 1 (trans) and isomer 2 (cis) if the polymer chain contains: (1) 50 repeat units. (ii) 200 repeat units. (b) Each isomer yields a different Raman spectrum. Assuming that the resulting Raman spectrum of the final polymer is the average of the spectra of the repeat units, compute the final Raman spectrum of the polymer containing 200 repeat units. Note: The Raman spectrum of each isomer is provided as excel file in the homework #2 folder