[Wien] SuperCell Calculation, space group and total energy

[Cara Watson]

Dear Wien2k users,

I want to do the calculation on modified TiC structure (displacing an
atom with respect to other atoms). So I used a 1*1*1 supercell with 8
inequivalent atoms (4 Ti 4 C). First time I run initialization with
all atoms sitting on their equilibrium positions, and "sgroup" told me
the space group is 225Fm3m, I accepted it and ran the calculation, I
got a total energy. Later on, I started another TiC structure by
shifting a Ti atom a little bit towards its neighboring C atom (but
fix all other 7 atoms) and ran the initialization, the sgroup told me
the space group is 99, I accepted it again and ran the calculation,
then got another total energy.

However, the confusion I got is that the total energy of the
equilibrium one is even higher than the energy of the shifted one
which is unphysical!

So I was wondering if these two total energies came from different
space groups are not actually comparable (e.g., difference energy
reference points)? Or do you have some explanations on this in your
mind?

Thanks!
Cara