I had a problem calculating the `formation energy per atom`

according to the formula in this link, and the result I got was significantly different from that given by the database. I calculate it as follows:

I use VASP to calculate the energy of the most stable element of each species, and then divide `energy without entropy`

in OUTCAR by the number of atoms to get `energy per atom`

. I treat this value as `μ`

in the formula.

I wonder what’s wrong with my calculation and whether the ‘energy per atom’ calculated by my method is `μ`

in the formula. In fact, the ‘energy per atom’ I get is also very different from the `energy per atom`

in the database.

PLS help, Thanks!