16
General Questions and Answers / Re: why?
« on: June 6, 2009, 03:16 »
Thank you very much. 
It is very valuable for me.
It is very valuable for me.
Show Posts
This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.
Pages: 1 [2]
17
General Questions and Answers / Re: why?
« on: June 5, 2009, 05:28 »
I find that if the periodicalty is dispear because i have doing the spin calculate.so the ldos is not periodically in the scattering region.(attched fig.2,3 they are for up and down) 2 cells of both the left and right is the probe.the 8 cells on center is scatting region.
while i do not add the spin to the syetem ,the ldos appers well periodicalty.(attched fig. 1.)
so i want to know whether the ldos i got fig 2,3 is reasonable?
for some one who studies in Green function mathord said that there would be some mistake in my ldos.because he think the two-probe system with addtion of 0 votage should be equall to the infinite graphene nanoribbon.so he think the ldos of two-probe system at fermi energy should also show its periodicalty in its scatting region.just like the fig 1 shows.
that confused me.and thanks a lot for your help.
while i do not add the spin to the syetem ,the ldos appers well periodicalty.(attched fig. 1.)
so i want to know whether the ldos i got fig 2,3 is reasonable?
for some one who studies in Green function mathord said that there would be some mistake in my ldos.because he think the two-probe system with addtion of 0 votage should be equall to the infinite graphene nanoribbon.so he think the ldos of two-probe system at fermi energy should also show its periodicalty in its scatting region.just like the fig 1 shows.
that confused me.and thanks a lot for your help.
18
General Questions and Answers / Re: why?
« on: June 4, 2009, 03:18 »
i calculate the ldos at fermi energy ,the transmission is 0 while the dos is not 0 but is close to 0.
the ldos should be peridoically all the same , thougt the system is no longer perfect.i mean that the scattering regin is periodically so its ldos should be periodically while i don not add the votage.is it true?
i calculate the transmission and dos,i want to analysis with the ldos at fremi energy.but the ldos looks like something matter,at first i can find its periodicity. i think there is something wrong in my system.but i dot know what is the problem.
can that we set the probe will break the graphene nanoribbon's periodicity or anything else?
the ldos should be peridoically all the same , thougt the system is no longer perfect.i mean that the scattering regin is periodically so its ldos should be periodically while i don not add the votage.is it true?
i calculate the transmission and dos,i want to analysis with the ldos at fremi energy.but the ldos looks like something matter,at first i can find its periodicity. i think there is something wrong in my system.but i dot know what is the problem.
can that we set the probe will break the graphene nanoribbon's periodicity or anything else?
19
General Questions and Answers / Re: why?
« on: June 3, 2009, 16:31 »
Is there any problity that it was caused by the optimize?
i want to know if i double of the probe's depth ,the vaule of dos and transmission will also be defferent from the calculate vaule with a shot probe?
i want to know if i double of the probe's depth ,the vaule of dos and transmission will also be defferent from the calculate vaule with a shot probe?
20
General Questions and Answers / why?
« on: June 3, 2009, 13:32 »
why the ldos of pefect graphene nanoribbon is not periodically?
in my opinion, the pefect graphene nanoribbon is periodically,so its ldos should also periodically.but the ldos i got is not periodically as i have attched.
in my opinion, the pefect graphene nanoribbon is periodically,so its ldos should also periodically.but the ldos i got is not periodically as i have attched.
21
General Questions and Answers / ATKError
« on: June 2, 2009, 06:49 »
i want to calculate the dos ,while i have optimized the structure. i have saved an opt.nc file in the optimize.and i used the initial density by restoring the opt.nc,also i save anther checkpoint file dos.nc.and it does not work for the error:
Traceback (most recent call last):
File "111spin-trans.py", line 345, in ?
runtime_parameters = runtime_parameters
ATKError: inverse(DZMatrix const &) : Could not LU factorize!
what can i do ?
and i have some other questions :
should i have to save the nc file of each calculation? or is it necessary for optimize?
is the nc file of opt equal to the nc file of scf?because we want to use the scf.nc file for farther calculation like the calculation of dos.i think may be it can save time of calculation.
Traceback (most recent call last):
File "111spin-trans.py", line 345, in ?
runtime_parameters = runtime_parameters
ATKError: inverse(DZMatrix const &) : Could not LU factorize!
what can i do ?
and i have some other questions :
should i have to save the nc file of each calculation? or is it necessary for optimize?
is the nc file of opt equal to the nc file of scf?because we want to use the scf.nc file for farther calculation like the calculation of dos.i think may be it can save time of calculation.
22
General Questions and Answers / Re: question about calculate the local_density_of_states
« on: May 25, 2009, 06:07 »
thank you for your reply.
I have modified my script accod according to your proposal.
It works well now.
but i have an other question :
can we export the date of LDOS directly?
I have modified my script accod according to your proposal.
It works well now.
but i have an other question :
can we export the date of LDOS directly?
23
General Questions and Answers / question about calculate the local_density_of_states
« on: May 24, 2009, 05:12 »
Hi:
i want to calculate the local_density_of_states of the structure that one fe atom adsorb on the graphene nanoribbon
part of my script is as follows:
local_density_of_states = calculateLocalDensityOfStates(
self_consistent_calculation = scf,
energy = 0.0*electronVolt,
quantum_number = ((0.0,0.0),Spin.Up),
green_function_infinitesimal = 1.0e-5*electronVolt
)
if processIsMaster(): file.addToSample(local_density_of_states, 'twoprobe_configuration', 'Local Density Of States')
local_density_of_states_1 = calculateLocalDensityOfStates(
self_consistent_calculation = scf,
energy = 0.0*electronVolt,
quantum_number = ((0.0,0.0),Spin.Down),
green_function_infinitesimal = 1.0e-5*electronVolt
)
if processIsMaster(): file.addToSample(local_density_of_states_1, 'twoprobe_configuration', 'Local Density Of States 1')
but i were been told that:NLValueError:One of or more atoms has a different number of orbitals.
how can i do ,if i want to calculate the LDOS of fermi energy?
what dose the quantum_number in "quantum_number = ((0.0,0.0),Spin.Down)"mean? dose it mean at a certain k point ,a certain energy such as fermi energy,the density_of_states of spin down state?or it means a series of k points?
i want to calculate the local_density_of_states of the structure that one fe atom adsorb on the graphene nanoribbon
part of my script is as follows:
local_density_of_states = calculateLocalDensityOfStates(
self_consistent_calculation = scf,
energy = 0.0*electronVolt,
quantum_number = ((0.0,0.0),Spin.Up),
green_function_infinitesimal = 1.0e-5*electronVolt
)
if processIsMaster(): file.addToSample(local_density_of_states, 'twoprobe_configuration', 'Local Density Of States')
local_density_of_states_1 = calculateLocalDensityOfStates(
self_consistent_calculation = scf,
energy = 0.0*electronVolt,
quantum_number = ((0.0,0.0),Spin.Down),
green_function_infinitesimal = 1.0e-5*electronVolt
)
if processIsMaster(): file.addToSample(local_density_of_states_1, 'twoprobe_configuration', 'Local Density Of States 1')
but i were been told that:NLValueError:One of or more atoms has a different number of orbitals.
how can i do ,if i want to calculate the LDOS of fermi energy?
what dose the quantum_number in "quantum_number = ((0.0,0.0),Spin.Down)"mean? dose it mean at a certain k point ,a certain energy such as fermi energy,the density_of_states of spin down state?or it means a series of k points?
Pages: 1 [2]