Elastic properties of one dimensional compounds

We have investigated the elastic properties of several one-dimensional compounds using a vibrating reed technique. A model calculation shows that a vanishing Young's modulus will occur for elastic one-dimensionality. TTF-TCNQ exhibits a small modulus which decreases with increasing temperature extrapolating to zero at T ≈ 500–700K. The uniaxial stress dependence of the metal-insulator transition temperature is calculated to be $\text{¦}\text{d}\text{T}{}_{\mathrm{c}}\text{/}\text{d}\text{σ¦ ～ (10 ± 5)}\text{K/bar}$. KCP shows a much higher modulus and a phase transformation at ～ 35 K.