Kink Deformation of (TMTSF)₂ClO₄ Single Crystal and Its Influence on Electrical Resistivity

Abstract

Mechanical kinks are formed in a needle crystal of bis (tetramethyltetraselenafulvalenium) perchlorate, (TMTSF) 2 ClO 4 , by applying stresses. The kink which has definite angle of 18.4° accompanies antikink with the same angle in the opposite direction. By the X-ray precession photograph, we show that the kink is ascribed to the mechanical twinning with the boundary on the (210) plane. The electrical resistivity measurements in a deformed part lying between the kink and antikink and in a region including the kink were carried out, but they did not show substantial difference compared with those in an underformed part. However, the kink which accompanies distortion in a molecular stack is considered to be one of causes of the resistance jump (stepwise increase in resistance), which is frequently observed during cooling.