Unbelievable gap & lambda

[jgSi1113]

Dear Dr. Kawamura,

When I used the sctk to calculated the critical temperature via calculation = "scdft_tc", the calculated results show that the Tc is 84 K (closed to the case of QE results), but the calculated gap (delta) is 0.48073E-08 meV. Why is there such a small gap? In addition, the lambda calculated by sctk is 0.30983E+01, bigger than the QE calculated one (2.09).

I am curious why sctk gives such a small gap and such a large gap. So would you kindly give me some suggestion to revised it?

Looking forward to your reply. Ang comments and suggestions are welcomed.

Thanks and Regards,
Jianguo Si

[jgSi1113]

Is it caused by insufficient k-point density during nscf calculation? The k-mesh I used is 242424, increasing it may induce memory related error for kel calculation under current computing resources.