IV curve nan (not a number)

[mantun]

I calculated the IV curve of a two-probe system with voltage ranging from -1V to 1V and found that the current at some voltage is nan (not a number). THe process is obtaining the scf nc files first, then computing the transmission spectrum and finally using the result analysis to get the IV curve. Can you tell me what's the problem?

[mantun]

no offical reply?

[Anders Blom]

More info needed. At the voltage giving problem, what does the transmission spectrum look like? Did all calculations converge? How do you compute the current (which tool - a VNL tool or a script)?

[mantun]

More info needed. At the voltage giving problem, what does the transmission spectrum look like? Did all calculations converge? How do you compute the current (which tool - a VNL tool or a script)?

The voltage range is -1 to 1 V, several votages give the problem. Even several voltage do give the current, the current is extremly small (about 1e-20 A). I used a loop to abtain the scf result, then a script is employed to compute the transmission spectrum. With the "IV analyzer" in vnl, the current is calculated. Surprising, I don't get the curve of transmission spectrum in the "IV analyzer". I turned to check the scf nc file, only a Warning -"The provided initial state parameter has no pre-calculated data.Proceeding without setting an initial state." -was found.

[Anders Blom]

Screenshots/plots would help, of the transmission and where the current is shown as NaN. Also, an idea of your system, ideally the scripts (by mail if secret).

[mantun]

Screenshots/plots would help, of the transmission and where the current is shown as NaN. Also, an idea of your system, ideally the scripts (by mail if secret).

i give you the screenshot of I-V curve in the vnl analyzer. Two scripts will be emailed to you. one is used to abtain scf results, and the other one is used to obtain transmission spectrum.

[mantun]

The forum staff think this result from the wrong geometry of two-probe system (that is the electrodes don't recover their bulk properties). But i haven't prove it. After i have done this, i will put my conclusion here.

[Rohit]

Please attach the two scripts which are  used to obtain scf results,and  transmission spectrum.......how can IV cuve be plotted using .nc file results....