One bad data in MP


Dear MP admin,

I would like to report a bad data in the MP database. It has the mp_id of “mp-649722” (
This data is definitely incorrect. MP reported it has ehull=703meV/atom and bandgap of zero. My chemical intuition tells me that it should be an insulator. Then, I performed the electronic structure calculation for this compound with MP parameters. I used the structure with ICSD-36324 as initial structure, which is the same as MP did. The calc. ehull and GGA-PBE band gap is 0.0144 eV/atom and 4.281 eV, respectively.

It is strange that MP did an incorrect calculation for this “simple” compound (nonmagnetic).


Dear zbwang,

Thank you for bringing this to our attention! We will investigate.

What procedure did you follow to calculate your ehull?


I first retrieve the entries in this (Na-Al-Si-O ) chemical space from MP (with MPRester()) and then use MaterialsProjectCompatibility() to process these entries + the calculated one and next, compute the ehull with PhaseDiagram().


Because you mentioned that you re-relaxed the ICSD structure yourself, would you mind sending me your INCAR, POSCAR, and final CONTCAR? I emailed you directly so you don’t have to post to the forum. Thanks.