Carbon tetrachloride: plastic properties.

The shear strength of solid carbon tetrachloride was measured from 187 degrees to 247 degrees K. A 25-percent discontinuity was observed at the solid- solid transition, at about 225 degrees K. This transition exhibited a distinct hysteresis. The shear strength of both the high- and low-temperature forms increased very rapidly as the temperature was lowered. There was no evidence of a rhombohedral high-temperature phase.