QuantumATK Forum

QuantumATK => General Questions and Answers => Topic started by: arpit on March 31, 2011, 13:20

Title: Regrading to brillion zone route
Post by: arpit on March 31, 2011, 13:20
sir i want to change brillion zone route...
currently it it is having two points G,Z.........
Title: Re: Regrading to brillion zone route
Post by: Anders Blom on March 31, 2011, 13:32
You can easily change the route. However, normally if you only get G,Z it means your system is 1D, so as long as it's directed along Z, no other point makes sense. If it's along another direction, you can use X or Y instead, correspondingly.
Title: Re: Regrading to brillion zone route
Post by: arpit on March 31, 2011, 14:00
sir i am rotating my sheet taking y as a axis...then suggest me some points...i m attaching an image of that structure..............
Title: Re: Regrading to brillion zone route
Post by: Anders Blom on March 31, 2011, 14:04
This system appears to be rotated at some angle (not 90) to the principal axes, and therefore doesn't really make sense. There shouldn't really be any reason to rotate the system, if you have built it in the Custom Builder for GNRs...
Title: Re: Regrading to brillion zone route
Post by: arpit on March 31, 2011, 14:09
sir but why....if i rotate it then what is the problem behind this.....can u plz explain it more clearly...i will be really thankful to you
Title: Re: Regrading to brillion zone route
Post by: Anders Blom on March 31, 2011, 14:12
I would put it differently: why rotate? :)
Title: Re: Regrading to brillion zone route
Post by: arpit on March 31, 2011, 14:15
sir i want to study the effect on band structure on rotating the graphene sheet.....but brillion zone route is by default..G,Z....
is their any other possible way using atk by which we can generate these kind of structure and study them,,,,
Title: Re: Regrading to brillion zone route
Post by: Anders Blom on March 31, 2011, 14:37
The band structure is rotationally invariant...
Title: Re: Regrading to brillion zone route
Post by: arpit on March 31, 2011, 14:40
but i found variation if i rotate it as i depict the figure in previous post..it means that my calculations are completely wrong...can we change the orientation of the graphene ribbon.......
Title: Re: Regrading to brillion zone route
Post by: Anders Blom on March 31, 2011, 14:47
Yes, the variation you are seeing are caused by breaking the ribbon, basically. When you rotate the coordinates internally inside the cell, it doesn't "fit" anymore in the cell, it's no longer a properly periodic structure.

If you want to change the orientation of the ribbon, you must rotate the unit cell too.

However, again, this doesn't change the band structure, except of course is you keep using the point Z, which corresponds to different a point in the rotated Brillouin zone compared to the original one.

I suggest you think a bit more carefully about what you are actually trying to achieve :)
Title: Re: Regrading to brillion zone route
Post by: arpit on March 31, 2011, 15:02
thank you sir....again you help me a lot.....and plz suggest me a some topics on graphene on which i can work...and sir from where i will gate the information about the paper published on graphene using atk.....plz suggest me a topic sir...

thanking you sir...........
Title: Re: Regrading to brillion zone route
Post by: Anders Blom on March 31, 2011, 15:18
You can find information on published work with ATK on graphene here:
http://quantumwise.com/documents/ATK_Publication_List.html?qsfield=graphene

If I was getting into this field myself, I would stay a little bit away from graphene, as this is a rather crowded space at the moment. How about something more original, like molybdenite (http://www.graphene-info.com/molybdenite-new-material-challenges-graphene) or silicene (http://www.graphene-info.com/silicene-new-atom-thin-honeycomb-material-made-silicon-atoms)?
Title: Re: Regrading to brillion zone route
Post by: arpit on April 1, 2011, 07:19
thank you sir....but i have given my thesis topic so i have to found something in graphene.....but thank you sir for your support and suggestions..
you are such a nice person...
thanking you sir