How to estimate anisotropic isothermal compressibility in GROMACS

GROMACS version: 2019.4
GROMACS modification: No

Dear GROMACS users and developers,

I have a question about methods of estimation of anisotropic isothermal compressibility by means of GROMACS. I know that gmx energy can estimate isothermal compressibility analysing fluctuations of volume during NPT simulation (M. P. Allen and D. J. Tildesley, Computer simulation of liquids, Oxford university press, 1989). But it is an isothermal compressibility for isotropic pressure coupling.

On the second thought, I found an alternative approach, estimating isothermal compressibility by linear approximation of dependency of volume logarithm on pressure. I tried this method, and obtained isothermal compressibility coinciding with ┬źcompressibility┬╗ value which was preset in *.mdp file. Is it correct method? Potentially, it may give anisotropic isothermal compressibility, if one used anisotropic pressure coupling varying one pressure component with constant other ones. I need estimation of isothermal compressibilities for simulation of smectic liquid crystals: such system is to have anisotropic compressibility.

Is there any correct way to estimate this value?