Dear all,

Thank you for your time. As I mentioned before I have taken my initial
parameters from a successful 2D MoS2 calculation. I am going to apply
your suggestions and If I was successful I would post the results
here.

Best regards,

On 1/11/15, Salvador Barraza-Lopez <[email protected]> wrote:
>  Adding to Andrei's response, you may want to ensure that your electronic
> bands and lattice parameters for bulk MoS2 do reproduce published results
> (you are probably trying to go too fast).
>  Best regards,
> -Salvador
> ________________________________________
> From: [email protected] [[email protected]] on behalf of
> [email protected] [[email protected]]
> Sent: Sunday, January 11, 2015 11:53 AM
> To: [email protected]
> Cc: siesta-l
> Subject: Re: [SIESTA-L] Help regarding structural relaxations for AMoS2NR
>
>> Dear all,
>>
>> I am trying to relax an armchair MoS2 nanoribbon. My initial
>> coordinates are taken from the MoS2 sheet. My .fdf file together with
>> my intial positions are attached. The problem is that after about 70
>> steps of CG relaxation, all the atoms are coming together and the
>> distances between atoms are much shorter than the initial ones. The
>> relaxed structure after about 70 steps is attached in elec.XV file. I
>> have successfully done relaxations for the MoS2 sheet but it seems
>> that I am not able to relax the nanoribbon. Any helps would be
>> apprecited.
>>
>> Bests,
>> Mohammad,
>>
>
> Dear Mohammad,
> some suggestions:
>
> 1. If you start a complicated system and a mess comes out,
> it might be a good idea to try to sort the things out. You have a bit
> too much of everything: many atoms, 70 CG steps, empty supercell whose
> dimensions you relax (that does not make sense anyway) etc.
> How about trying just bulk MoS2 first?
> Then, if it not not quite to expectations, you can pull different
> levers: basis, cutoffs, XC etc. If everything works fine, you can
> proceed to your nanoribbons or whatever.
>
> 2. If you expect help on a quite vague issue,
> it might be a good idea to provide at least the output file.
> There are not many cases when the error is seen right away from
> the input file, and to expect the colleagues to repeat your calculations
> just out of curiosity might be too optimistic.
>
> Have a nice day,
>
> Andrei Postnikov
>

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