[Pw_forum] Interpretation of electron phonon coupling

[Elio Physics]

Hello everyone.  I still have some confusion regarding the convergence of the calculations of the electron phonon coupling, lambda.
I have tested this for a simple system such as bilayer graphene... I have chosen a cutoff energy of 60Ry and a cutoff density ecutrho of 540 Ry ( 9 times the value of ecutoff because my pseudo potential is ultrasoft C.pbe-rrkjus). Also the k grid was chosen to be 36 x 36 x1.  I have verified then convergence of the total energy with respect to the cutoff energy and the number of k-grid points before starting the calculations and everything seemed pretty fine.  Calculations were done for 19 phonon points and extrapolation later followed (in matdyn I had a 120 x 120 x1 phonon grid). Finally , I got the following results:
 Broadening   0.0050 lambda       0.0163 Broadening   0.0100 lambda       0.0383  Broadening   0.0150 lambda       0.0328  Broadening   0.0200 lambda       0.0209  Broadening   0.0250 lambda       0.0147  Broadening   0.0300 lambda       0.0133 Broadening   0.0350 lambda       0.0149  Broadening   0.0400 lambda       0.0185  Broadening   0.0450 lambda       0.0234  Broadening   0.0500 lambda       0.0287 
I cannot see any plateau here as I was told in an earlier e-mail. Which one of these values is the convergent electron phonon coupling, if it is convergent at all? Any help can be appreciated to clear this misunderstanding.

Thank you in advance
ElioUniversity of RondoniaBrazil 



 		 	   		  
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