Certainly! Here’s the English translation of your refined question:
Subject: Question on Discrepancy in NbC Formation Energy Calculation Compared to Materials Project
Hello,
When calculating the formation energy of NbC using Materials Project data, I found a significant difference between my result and the value given on the MP website.
Here are the details:
- The mp-ids and total energies I used are:
- NbC: mp-910, E(NbC) = –20.2463 eV
- Nb: mp-75, E(Nb) = –10.1013 eV
- C: mp-3347313, E(C) = –9.9472 eV
Based on this, I calculated the formation energy per atom as follows:
Ef = [E(NbC) – E(Nb) – E(C)] / 2 = [–20.2463 – (–10.1013 + –9.9472)] / 2 = –0.099 eV/atom
However, the formation energy reported by the Materials Project is –0.536 eV/atom, which is quite different.
Could someone please help me understand the source of this difference? Am I missing some correction, or perhaps using incorrect reference structures or energies?
Thank you very much for your help!
Best wishes,
Yuefeng Zhang