Isotope effect in BEDT-TTF based organic superconductors

Abstract The results of our comprehensive isotope effect studies, in which seven different isotopically labeled (involving 13 C, 34 S and 2 H labeling) BEDT-TTF derivatives and isotopically labeled anion [Cu( 15 N 13 CS) 2 ] − were utilized, are summarized. For the first time, convincing evidence for a genuine BCS-like mass isotope effect in an organic superconductor is revealed in our studies.