QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: njuxyh on August 31, 2016, 04:03

Title: the scf of iv-curve in some bias did not convengency, some did converge
Post by: njuxyh on August 31, 2016, 04:03

Hi :
I calculated the iv-curve under 0-2 V, But I found under 1.4,1.6,0.6,0.4.0.2 V the scf calculation did converge, but other bias point did not converge such 0.8,1.0.1.2 .1.8.2.0.
  217   S   [   3.337 ,  19.732 ,  67.456 ]    6.82742   0.82742              |
|  218   S   [   2.275 ,  23.070 ,  67.460 ]    6.36327   0.36327              |
|  219   S   [   4.364 ,  23.102 ,  67.461 ]    6.36487   0.36487              |
+------------------------------------------------------------------------------+
|  99 E =  -356.72 dE =  3.048208e-04 dH =  1.026967e-02                       |
+------------------------------------------------------------------------------+
################################################################################
#                                                                              #
# Warning: The calculation did not converge to the requested tolerance!        #
#                                                                              #
################################################################################
+------------------------------------------------------------------------------+
|                                                                              |
| NEGF DFT Calculation  [Finished Sat Aug 27 18:33:23 2016]                    |
|                                                                              |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
|                                                                              |
| Device DFT Calculation  [Finished Sat Aug 27 18:33:23 2016]                  |
|                                                                              |
+------------------------------------------------------------------------------+
+------------------------------------------------------------------------------+
|                                                                              |
| Transmission Spectrum Analysis                                               |
|                                                                              |
+------------------------------------------------------------------------------+

                            |--------------------------------------------------|
Calculating Transmission   : ==================================================
                                                                                           


 so I am wondering how to set the parameter to continue to recalculated the transmission spectrum under converge bias 0.8,1.0.1.2 and 1.8.2.0 V.
my current calculation only has one checkpoint file which including the whole bias 0-2 V.
 

Title: Re: the scf of iv-curve in some bias did not convengency, some did converge
Post by: Daniele Stradi on August 31, 2016, 10:33

Hi,

it is quite difficult to say how to modify the convergence parameters without seeing the system and the *.py input script.
Could you attach it here or send it via a private mail?

Thanks,
Daniele