Equation-of-state, sound speed, and reshock of shock-compressed fluid carbon dioxide
L. E. Crandall, J. R. Rygg, D. K. Spaulding, Margaret Huff, M. C. Marshall, D. N. Polsin, Raymond Jeanloz, T. R. Boehly, Mohamed Zaghoo, B. J. Henderson, S. Brygoo, P. M. Celliers, J. H. Eggert, D. E. Fratanduono, Amy Lazicki, M. Millot, G. W. Collins
Abstract
Mechanical equation-of-state data of initially liquid and solid CO2 shock-compressed to terapascal conditions are reported. Diamond-sapphire anvil cells were used to vary the initial density and state of CO2 samples that were then further compressed with laser-driven shock waves, resulting in a data set from which precise derivative quantities, including Grüneisen parameter and sound speed, are determined. Reshock states are measured to 800 GPa and map the same pressure-density conditions as the single shock using different thermodynamic paths. The compressibility data reported here do not support current density-functional-theory calculations, but are better represented by tabular equation-of-state models.