SEARCH Articles Figures Tables 2-Phenyl butyric acid Butyric 3-methyl-3-phenyl Butyric 3-phenyl Butyric acid, «,7-dicyano-<»-phenyl Butyric acid, «,7-dicyano-<»-phenyl ETHYL ESTER Methyl -2-hydroxy-4-phenyl butyrate Phenyl C61-butyric acid methyl ester Phenyl-C61-butyric acid methyl ester PCBM) Phenyl-C6i-butyric acid methyl ester Phenyl-C6i-butyric acid methyl ester PCBM) Phenyl-Cgi-butyric acid methyl ester (PCBM