Tejero and Cuesta hard disk equation of state

The Tejero and Cuesta hard disk equation of state is given by (Ref. 1 Eq. 3.10)

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where

Failed to parse (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle C_{1}}	0
Failed to parse (Conversion error. Server ("https://wikimedia.org/api/rest_") reported: "Cannot get mml. Server problem."): {\displaystyle C_{2}}	0.128018
$C_{3}$	0.0018188
$C_{4}$	-0.72553
$C_{5}$	2.52783
$C_{6}$	-2.4945

Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \eta} is the packing fraction and Z is the compressibility factor.

References

1. C. F. Tejero and J. A. Cuesta "Hard-sphere and hard-disk freezing from the differential formulation of the generalized effective liquid approximation", Physical Review E 47 pp. 490-495 (1993)