[Pw_forum] error in pwcond.x calculations

[Gabriele Sclauzero]

ErJun Kan wrote:
> I will try different ibrav to see the difference.

As Alexander pointed you can even use monoclinic cells, of which the orthorombic cells 
should be a subset (with cos(ab)=0), if I'm not mistaken.

> 
>>> $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$
>>> !and the pwcond.x calculation part:
>>>  &inputcond
>>>     outdir='./',
>>>         prefixl='gan',
>>>     prefixs = 'gan'
>> Another problem could be here: why do you specify the same prefix for both left
> lead and 
>> scattering region? Are you sure you understood the meaning of those prefixes? If
> not, 
>> please try to read some documentation and if it's still not clear you can ask to
> this forum.
>  In my case, I will use the same leads, but with different scattering region. 

And so why do you specify the same prefix for both the left lead and the scatetring 
region??? (the right lead is assumed to be identical to the left one, in your input)
Please first have a look at the examples in the examples/ directory and try to practice 
with them (and understand the meaning of parameters and input keywords).


> The
> only ambiguous point is whether the leads can be a semiconductor or insulator?

In principle the leads should be metallic, I don't know if this formulation of ballistic 
transport makes sense with semiconductors or insulators.
In practice the transmission calculations should be feasible, but it makes no sense to use 
the same cell as both the lead AND the scattering region (which have conceptually 
different meanings!).
You should make clear to yourself what you want to calculate, first of all.

GS

> 
>>
> 
> =============================================================
>  Erjun Kan
>  Department of Chemistry, North Carolina State University
>  Raleigh, North Carolina, USA
>  E-mail: erjunkan at mail.ustc.edu.cn  or
>              ekan at ncsu.edu
> ============================================================= 
> 
> 
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