RE: [SIESTA-L] How does siesta calculate bands in a gamma-point-only scf calculation?
Thanks. That’s exactly what I needed. Chong From: Nick Papior<mailto:nickpap...@gmail.com> Sent: Saturday, January 29, 2022 1:04 PM To: siesta-l<mailto:siesta-l@uam.es> Subject: Re: [SIESTA-L] How does siesta calculate bands in a gamma-point-only scf calculation? Hi, Simply add this to your fdf file: ForceAuxCell true Den fre. 28. jan. 2022 kl. 22.01 skrev Chong Wang mailto:ch-w...@outlook.com>>: Dear siesta developers, I am trying to read HSX file and calculate corresponding band structure myself (because I need wave function information). The HSX file is generated with a gamma-point-only scf calculation, and thus it is necessary to do some modification to the `xij` variable. For example, suppose I have a ten-atom chain: 1-2-3-4-5-6-7-8-9-10 A gamma point calculation will introduce hopping between atom 1 and atom 10 (<1|H|10>) due to periodic boundary condition. To calculate band structure, it is necessary to realize the hopping is across the cell boundaries. Currently, `xij` is the vector pointing from 1 to 10 in the home unit cell: 1>10. Some modification is needed such that it points to the left side of the unit cell: 10<-1-2-3-4-5-6-7-8-9-10. I can do this modification myself, but I guess there is already a subroutine in siesta that does this trick. Where is it? Best Chong Wang -- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) -- Kind regards Nick -- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/)
Re: [SIESTA-L] How does siesta calculate bands in a gamma-point-only scf calculation?
Hi, Simply add this to your fdf file: ForceAuxCell true Den fre. 28. jan. 2022 kl. 22.01 skrev Chong Wang : > Dear siesta developers, > > > > I am trying to read HSX file and calculate corresponding band structure > myself (because I need wave function information). The HSX file is > generated with a gamma-point-only scf calculation, and thus it is necessary > to do some modification to the `xij` variable. > > > > For example, suppose I have a ten-atom chain: > > 1-2-3-4-5-6-7-8-9-10 > > > > A gamma point calculation will introduce hopping between atom 1 and atom > 10 (<1|H|10>) due to periodic boundary condition. To calculate band > structure, it is necessary to realize the hopping is across the cell > boundaries. Currently, `xij` is the vector pointing from 1 to 10 in the > home unit cell: > > 1>10. > > Some modification is needed such that it points to the left side of the > unit cell: > > 10<-1-2-3-4-5-6-7-8-9-10. > > > > I can do this modification myself, but I guess there is already a > subroutine in siesta that does this trick. Where is it? > > > > Best > > Chong Wang > > > > -- > SIESTA is supported by the Spanish Research Agency (AEI) and by the > European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) > -- Kind regards Nick -- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/)
[SIESTA-L] How does siesta calculate bands in a gamma-point-only scf calculation?
Dear siesta developers, I am trying to read HSX file and calculate corresponding band structure myself (because I need wave function information). The HSX file is generated with a gamma-point-only scf calculation, and thus it is necessary to do some modification to the `xij` variable. For example, suppose I have a ten-atom chain: 1-2-3-4-5-6-7-8-9-10 A gamma point calculation will introduce hopping between atom 1 and atom 10 (<1|H|10>) due to periodic boundary condition. To calculate band structure, it is necessary to realize the hopping is across the cell boundaries. Currently, `xij` is the vector pointing from 1 to 10 in the home unit cell: 1>10. Some modification is needed such that it points to the left side of the unit cell: 10<-1-2-3-4-5-6-7-8-9-10. I can do this modification myself, but I guess there is already a subroutine in siesta that does this trick. Where is it? Best Chong Wang -- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/)