ANISOTROPY OF MAGNETOCONDUCTIVITY IN ORIENTED POLY(ACETYLENE) DOPED WITH IODINE

In this study we have observed that the sign of magnetoconductivity (M C) changes according to the chain direction (i.e. drawing direction) w ith respect to the field. When the chains are parallel or perpendicula r to the field the MC is negative or positive, respectively. The direc tion of the current does not alter the sign of the MC. The measurement s were made in the five different combinations of the current, the cha in and the field direction. Our observation is in qualitative agreemen t with 3-D weak localization theory with anisotropic effective mass te nsor.