Re: [SIESTA-L] Thoughts on PDOS siesta vs PDOS tbtrans
Thank you again for the reply Nick. I was wondering if I calculate a system made of gold electrodes but without including gold into the scattering region. But still managed to get PDOS SIESTA and PDOS TbTRANS (V=0) identical, would that be ok? Or is having gold in the scattering region mandatory? Thank you and eager to reading your reply. EL-ABed El-abed Haidar | Doctor of Philosophy (Science) Condensed Matter Theory (CMT) Group | School of Physics THE UNIVERSITY OF SYDNEY | NSW | 2006 From: siesta-l-requ...@uam.es on behalf of Nick Papior Sent: Wednesday, 3 July 2019 6:05 AM To: siesta-l Subject: Re: [SIESTA-L] Thoughts on PDOS siesta vs PDOS tbtrans Den tir. 2. jul. 2019 kl. 22.01 skrev El-abed Haidar mailto:ehai2...@uni.sydney.edu.au>>: THank you again for the reply Nick I wanted to ask you then if PDOS siesta vs PDOS Tbtrans(V=0) are NOT similar which means that the system is not sufficiently built: Does that mean all results (T(E), current and PDOS) are not physical? Probably yes, this would be a first guess. I.e. you should try and increase the system size. IF so could it be because Transiesta and thus Tbtrans are z coordinate sensitive (in a sense that I should always build my system in an increasing z order)? They are not z-coordinate sensitive. Thank you and looking forward to your reply! EL-abed El-abed Haidar | Doctor of Philosophy (Science) Condensed Matter Theory (CMT) Group | School of Physics THE UNIVERSITY OF SYDNEY | NSW | 2006 From: siesta-l-requ...@uam.es<mailto:siesta-l-requ...@uam.es> mailto:siesta-l-requ...@uam.es>> on behalf of Nick Papior mailto:nickpap...@gmail.com>> Sent: Monday, 24 June 2019 8:23 PM To: siesta-l Subject: Re: [SIESTA-L] Thoughts on PDOS siesta vs PDOS tbtrans In general, A 0 bias calculation should yield a somewhat equivalent PDOS in siesta vs. tbtrans. If this is the case it means that you have set up your system in a sufficient manner. This is to say that the electrodes already screen off the junction sufficiently (please spend some time on why this is)! For non-zero bias they are (should) be different. Den fre. 21. jun. 2019 kl. 22.01 skrev El-abed Haidar mailto:ehai2...@uni.sydney.edu.au>>: Good evening all, I was wondering if anyone could give some insight on the difference between PDOS calculated in siesta as a DFT run vs PDOS calculated in tbtrans as a DFT+NEGF run. Should i expect for example PDOS to be different? Any computational or physical insight would be highly appreciated. Thank you and looking forward to the comments. EL-abed El-abed Haidar | Doctor of Philosophy (Science) Condensed Matter Theory (CMT) Group | School of Physics THE UNIVERSITY OF SYDNEY | NSW | 2006 -- Kind regards Nick -- Kind regards Nick
Re: [SIESTA-L] Thoughts on PDOS siesta vs PDOS tbtrans
Den tir. 2. jul. 2019 kl. 22.01 skrev El-abed Haidar < ehai2...@uni.sydney.edu.au>: > THank you again for the reply Nick > I wanted to ask you then if PDOS siesta vs PDOS Tbtrans(V=0) are NOT > similar which means that the system is not sufficiently built: Does that > mean all results (T(E), current and PDOS) are not physical? > Probably yes, this would be a first guess. I.e. you should try and increase the system size. > IF so could it be because Transiesta and thus Tbtrans are z coordinate > sensitive (in a sense that I should always build my system in an increasing > z order)? > They are not z-coordinate sensitive. > Thank you and looking forward to your reply! > EL-abed > > El-abed Haidar | Doctor of Philosophy (Science) > Condensed Matter Theory (CMT) Group > | School of Physics > THE UNIVERSITY OF SYDNEY | NSW | 2006 > > -- > *From:* siesta-l-requ...@uam.es on behalf of > Nick Papior > *Sent:* Monday, 24 June 2019 8:23 PM > *To:* siesta-l > *Subject:* Re: [SIESTA-L] Thoughts on PDOS siesta vs PDOS tbtrans > > In general, > > A 0 bias calculation should yield a somewhat equivalent PDOS in siesta vs. > tbtrans. If this is the case it means that you have set up your system in a > sufficient manner. This is to say that the electrodes already screen off > the junction sufficiently (please spend some time on why this is)! > For non-zero bias they are (should) be different. > > Den fre. 21. jun. 2019 kl. 22.01 skrev El-abed Haidar < > ehai2...@uni.sydney.edu.au>: > > Good evening all, > I was wondering if anyone could give some insight on the difference > between PDOS calculated in siesta as a DFT run vs PDOS calculated in > tbtrans as a DFT+NEGF run. > Should i expect for example PDOS to be different? Any computational or > physical insight would be highly appreciated. > Thank you and looking forward to the comments. > EL-abed > > El-abed Haidar | Doctor of Philosophy (Science) > Condensed Matter Theory (CMT) Group > | School of Physics > THE UNIVERSITY OF SYDNEY | NSW | 2006 > > > > -- > Kind regards Nick > -- Kind regards Nick
Re: [SIESTA-L] Thoughts on PDOS siesta vs PDOS tbtrans
THank you again for the reply Nick I wanted to ask you then if PDOS siesta vs PDOS Tbtrans(V=0) are NOT similar which means that the system is not sufficiently built: Does that mean all results (T(E), current and PDOS) are not physical? IF so could it be because Transiesta and thus Tbtrans are z coordinate sensitive (in a sense that I should always build my system in an increasing z order)? Thank you and looking forward to your reply! EL-abed El-abed Haidar | Doctor of Philosophy (Science) Condensed Matter Theory (CMT) Group | School of Physics THE UNIVERSITY OF SYDNEY | NSW | 2006 From: siesta-l-requ...@uam.es on behalf of Nick Papior Sent: Monday, 24 June 2019 8:23 PM To: siesta-l Subject: Re: [SIESTA-L] Thoughts on PDOS siesta vs PDOS tbtrans In general, A 0 bias calculation should yield a somewhat equivalent PDOS in siesta vs. tbtrans. If this is the case it means that you have set up your system in a sufficient manner. This is to say that the electrodes already screen off the junction sufficiently (please spend some time on why this is)! For non-zero bias they are (should) be different. Den fre. 21. jun. 2019 kl. 22.01 skrev El-abed Haidar mailto:ehai2...@uni.sydney.edu.au>>: Good evening all, I was wondering if anyone could give some insight on the difference between PDOS calculated in siesta as a DFT run vs PDOS calculated in tbtrans as a DFT+NEGF run. Should i expect for example PDOS to be different? Any computational or physical insight would be highly appreciated. Thank you and looking forward to the comments. EL-abed El-abed Haidar | Doctor of Philosophy (Science) Condensed Matter Theory (CMT) Group | School of Physics THE UNIVERSITY OF SYDNEY | NSW | 2006 -- Kind regards Nick
Re: [SIESTA-L] Thoughts on PDOS siesta vs PDOS tbtrans
You are correct. More k-points for transmission / Dos calculations using tbtrans. On Tue, 25 Jun 2019, 22:00 El-abed Haidar, wrote: > Thank you very much for the reply. This is very interesting because I > never knew that PDOS siesta should to good extent match PDOS Tbtrans at > V=0. > My question would be then in order to compare both results they should > have really almost the same parameters. But one parameter i feel will be > different is usually the K points because in Siesta DFT you would first > create the charge density with certain k points. Then increase the K points > to find PDOS or am I wrong? > Thank you again Nick really appreciate your explanations. > EL-abed > > El-abed Haidar | Doctor of Philosophy (Science) > Condensed Matter Theory (CMT) Group > | School of Physics > THE UNIVERSITY OF SYDNEY | NSW | 2006 > > -- > *From:* siesta-l-requ...@uam.es on behalf of > Nick Papior > *Sent:* Monday, 24 June 2019 8:23 PM > *To:* siesta-l > *Subject:* Re: [SIESTA-L] Thoughts on PDOS siesta vs PDOS tbtrans > > In general, > > A 0 bias calculation should yield a somewhat equivalent PDOS in siesta vs. > tbtrans. If this is the case it means that you have set up your system in a > sufficient manner. This is to say that the electrodes already screen off > the junction sufficiently (please spend some time on why this is)! > For non-zero bias they are (should) be different. > > Den fre. 21. jun. 2019 kl. 22.01 skrev El-abed Haidar < > ehai2...@uni.sydney.edu.au>: > > Good evening all, > I was wondering if anyone could give some insight on the difference > between PDOS calculated in siesta as a DFT run vs PDOS calculated in > tbtrans as a DFT+NEGF run. > Should i expect for example PDOS to be different? Any computational or > physical insight would be highly appreciated. > Thank you and looking forward to the comments. > EL-abed > > El-abed Haidar | Doctor of Philosophy (Science) > Condensed Matter Theory (CMT) Group > | School of Physics > THE UNIVERSITY OF SYDNEY | NSW | 2006 > > > > -- > Kind regards Nick >
Re: [SIESTA-L] Thoughts on PDOS siesta vs PDOS tbtrans
Thank you very much for the reply. This is very interesting because I never knew that PDOS siesta should to good extent match PDOS Tbtrans at V=0. My question would be then in order to compare both results they should have really almost the same parameters. But one parameter i feel will be different is usually the K points because in Siesta DFT you would first create the charge density with certain k points. Then increase the K points to find PDOS or am I wrong? Thank you again Nick really appreciate your explanations. EL-abed El-abed Haidar | Doctor of Philosophy (Science) Condensed Matter Theory (CMT) Group | School of Physics THE UNIVERSITY OF SYDNEY | NSW | 2006 From: siesta-l-requ...@uam.es on behalf of Nick Papior Sent: Monday, 24 June 2019 8:23 PM To: siesta-l Subject: Re: [SIESTA-L] Thoughts on PDOS siesta vs PDOS tbtrans In general, A 0 bias calculation should yield a somewhat equivalent PDOS in siesta vs. tbtrans. If this is the case it means that you have set up your system in a sufficient manner. This is to say that the electrodes already screen off the junction sufficiently (please spend some time on why this is)! For non-zero bias they are (should) be different. Den fre. 21. jun. 2019 kl. 22.01 skrev El-abed Haidar mailto:ehai2...@uni.sydney.edu.au>>: Good evening all, I was wondering if anyone could give some insight on the difference between PDOS calculated in siesta as a DFT run vs PDOS calculated in tbtrans as a DFT+NEGF run. Should i expect for example PDOS to be different? Any computational or physical insight would be highly appreciated. Thank you and looking forward to the comments. EL-abed El-abed Haidar | Doctor of Philosophy (Science) Condensed Matter Theory (CMT) Group | School of Physics THE UNIVERSITY OF SYDNEY | NSW | 2006 -- Kind regards Nick
Re: [SIESTA-L] Thoughts on PDOS siesta vs PDOS tbtrans
In general, A 0 bias calculation should yield a somewhat equivalent PDOS in siesta vs. tbtrans. If this is the case it means that you have set up your system in a sufficient manner. This is to say that the electrodes already screen off the junction sufficiently (please spend some time on why this is)! For non-zero bias they are (should) be different. Den fre. 21. jun. 2019 kl. 22.01 skrev El-abed Haidar < ehai2...@uni.sydney.edu.au>: > Good evening all, > I was wondering if anyone could give some insight on the difference > between PDOS calculated in siesta as a DFT run vs PDOS calculated in > tbtrans as a DFT+NEGF run. > Should i expect for example PDOS to be different? Any computational or > physical insight would be highly appreciated. > Thank you and looking forward to the comments. > EL-abed > > El-abed Haidar | Doctor of Philosophy (Science) > Condensed Matter Theory (CMT) Group > | School of Physics > THE UNIVERSITY OF SYDNEY | NSW | 2006 > > -- Kind regards Nick
