Photoconductivity threshold of supercritical xenon fluids doped with anthracene as a function of fluid density

Abstract

The photoconductivity threshold energy I f of supercritical xenon fluids doped with anthracene was measured as a function of fluid density N from 0.03 × 10 21 to 7.5 × 10 21 cm −3. For high densities ( N⩾ 7 × 10 21 cm −3), I f values were well described by the equation I f= I g+ V 0+ P, where I g is the gas-phase ionization potential of anthracene, V 0 the conduction band energy in the xenon fluids and P the polarization energy of an anthracene positive ion. The value of the ionic radius, 0.325 nm, used for the calculation of P is derived from literature data on I f in non-polar liquids. The deviation of measured I f values from the above expression is discussed.