S1 Supporting Information Enhanced Organic Solar Cell Performance by Lateral Side Chain Engineering on BenzodithiopheneBased Small Molecules Dhananjaya Patra a,bξ , Widhya Budiawan a, c, dξ , TzuYen Huang a, e , KungHwa Wei f , PenCheng Wang c , KuoChuan Ho e, g , Mohammed AlHashimi b and ChihWei Chu a,h, * a Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan (R.O.C.) 11529 b Department of Chemistry, Texas A&M University at Qatar, P.O. Box 23874, Doha, Qatar c Department of Engineering and System Science, National TsingHua University, Hsinchu, Taiwan (R.O.C.)30013 d Nanoscience and Technology Program, Taiwan International Graduate Program, Academia Sinica and National TsingHua University, Taiwan(R.O.C.) 11529 e Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan (R.O.C.) 10617 f Department of Materials Science and Engineering, National ChiaoTung University, Hsinchu, Taiwan (R.O.C.) 30013 g Institute of Polymer Science and Engineering, National Taiwan University, Taipei, Taiwan (R.O.C.) 10617 h College of Engineering, Chang Gung University, Taoyuan 33302, Taiwan ξ D.P. and W.B. contributed equally to this paper. *email : gchu@gate.sinica.edu.tw