Error energy minimization - Martini

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GROMACS version: 2023.2
GROMACS modification: No

Hi! I am trying to simulate a liposome with a protein inside with Martini. I have already created the vesicle with TS2CG and minimized it (everything fine). For the protein, I also have it minimized. I joined both .gro files and in vdm the system looks well. But when I was trying to minimize the energy of the entire system, I had problems with the gmx mdrun:
Fatal error:
Function type Restr. Angles does not currently support being perturbed in free energy calculations

I was trying to use the same .mdp file for minimization that I used for the liposome.
I also tried with other .mdp files. I don’t have experience making a custom .mdp file. Could you please help me?

em_1.mdp (1.2 KB)

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Firstly, are you sure you need free-energy perturbations for your energy minimization? Running at init-lambda = 0.01 with couple-lambda0 = vdw-q is almost the same as running without free energy perturbations, but slower.

However, the error message comes from your restraints. Check the restraints in your topology parameters (often included as separate files). Are there are restraint angles with different lambda A and lambda B states? That’s not supported in free energy calculations.