Pressure effect on the charge-density-wave formation in2H−NbSe2and correlation between structural instabilities and superconductivity in unstable solids

Abstract

The hydrostatic pressure dependence of the charge-density-wave onset temperature $T_0$ in $2H-\mathrm{N}\mathrm{b}{\mathrm{Se}}_2$ was measured up to 20 kbar. $\frac{d{T}_0}{\mathrm{dP}}$ was found to be -(3.3 ± 0.2) × ${10}^{-4\mathrm{}}$ K ${\mathrm{bar}}^{-1\mathrm{}}$. An examination of existing high - pressure data concerning structural instabilities and superconductivity in both layered and isotropic compounds is made.