Messages

1

General Questions and Answers / CNT Coordinates

« on: August 9, 2011, 15:56 »

Hello Everyone
I am using ATK VNL 2008.10 version. I want to study variation in enerty of  CNT with C-C bond lengty. In the nanotube grower tool distance between carbon atoms can be modified and correspondingly coordinates can be saved but I want to do this in the python program so is there any script  available to do so? I have searched it on forum but I didn't find it. Please help me

2

General Questions and Answers / Calculation of optimized surface structure

« on: July 25, 2011, 12:54 »

Hello Everyone
I want to  calculate optimized structure of the surface[110] of W.
I have attached my file. By running it I am getting following error:

Traceback (most recent call last):
  File "c:/docume~1/cct/locals~1/temp/tmpyc5cps.nl", line 98, in ?
    scf=kohnsham_method.apply(my_cell)
ATKError: solveHermitianGeneralizedEigenProblem : Failed to diagonalize matrix!
Terminated Abnormally

Please help me to solve it.
I want to ask
-Is Vacuum extension of my structure is wrong or there is any other problem with my unit cell or with k point specification.
-What is the function of solveHermitianGeneralizedEigenProblem and why it fails to diagonalize matrix for my structure.

Thanks in advance

3

General Questions and Answers / Re: Band structure of clusters

« on: March 1, 2011, 05:02 »

Please tell me also that which formula is used by ATK to obtain the band structure.

4

General Questions and Answers / Re: Band structure of clusters

« on: March 1, 2011, 05:00 »

But it is a fact that as size decreases the band gap increases. And band gap is significantly increased at nano level as compared to bulk.
Band gap have meaning only when there some band exists. Hence there must be some band structure or energy levels for nanoclusters.

I have tried to calculate it as molecular system but when i try to drag crystal structure from bulk builder to molecular builder than nothing happens.
Please solve my problem.

5

General Questions and Answers / Band structure of clusters

« on: February 28, 2011, 06:22 »

Dear all
       Please tell me that how to calculate fermi energy and band structure of small nano clusters in place of bulk configuration(which provide bulk band structure and band gap) using 2008.10 version.
Also provide some theoretical material to learn detailed analysis of cluster properties using band structure.
Your help is very valuable for me.

Thanks

6

General Questions and Answers / Re: Fermi Energy Shifting

« on: January 17, 2011, 06:12 »

Unless you changed any advanced options, the Fermi level is the zero energy in the band structure.

I am using ATK + VNL 2008.10 version. There is no such advanced option

7

General Questions and Answers / Fermi Energy Shifting

« on: January 11, 2011, 12:10 »

By  calculating band structure of ZnO using VNL, I got band structrue in which energy is distributed from negative to positive and 0 energy is in between them. Fermi energy is negative nearly -4.02.

Please tell me that in the result browser's output band structure figure, 0 energy corresponds to fermi energy or value at -4.02 is femi energy?

If it is at -4.02 than I must shift whole band structure by setting fermi energy 0.

8

General Questions and Answers / c:/users/nano/appdata/local/temp/tmpuqo2g4.nl

« on: December 23, 2010, 16:31 »

I am getting following error :


Traceback (most recent call last):
  File "c:/users/nano/appdata/local/temp/tmpuqo2g4.nl", line 487, in ?
    runtime_parameters = runtime_parameters
ATKError: bad allocation
Terminated Abnormally

I have checked my c drive but there is no such folder or file. Than what is meaning of line 487.

Also please tell me about mistake of my script


My script is:


from ATK.TwoProbe import *
from ATK.MPI import processIsMaster

# Generate time stamp
if processIsMaster():
    import platform, time
    print '#',time.ctime()
    print '#',platform.node(),platform.platform()+'\n'

# Opening vnlfile
if processIsMaster(): file = VNLFile('C:/Users/Nano/Desktop/apt chrismas/apt1.vnl')

# Scattering elements and coordinates
scattering_elements = [Platinum, Platinum, Platinum, Platinum,
                       Platinum, Platinum, Platinum, Platinum,
                       Carbon,   Carbon,   Carbon,   Carbon,   
                       Carbon,   Carbon,   Carbon,   Carbon,   
                       Carbon,   Carbon,   Carbon,   Carbon,   
                       Carbon,   Carbon,   Carbon,   Carbon,   
                       Carbon,   Carbon,   Carbon,   Carbon,   
                       Platinum, Platinum, Platinum, Platinum,
                       Platinum, Platinum]
scattering_coordinates = [[  0.        ,   0.        ,   7.84800005],
                          [  0.        ,   2.77468705,   7.84800005],
                          [  2.77468705,   0.        ,   7.84800005],
                          [  2.77468705,   2.77468705,   7.84800005],
                          [  1.38734353,   4.1620307 ,   9.81000042],
                          [  1.38734353,   1.38734353,   9.81000042],
                          [  4.1620307 ,   4.1620307 ,   9.81000042],
                          [  4.1620307 ,   1.38734353,   9.81000042],
                          [  4.31650639,   2.95859623,  13.7       ],
                          [  4.31650639,   2.95859623,  16.16297622],
                          [  4.31650639,   2.95859623,  18.62595243],
                          [  2.95859623,   4.31650639,  14.93148811],
                          [  2.95859623,   4.31650639,  17.39446445],
                          [  1.60068655,   2.95859623,  13.7       ],
                          [  1.60068655,   2.95859623,  16.16297622],
                          [  1.60068655,   2.95859623,  18.62595243],
                          [  2.95859623,   1.60068655,  14.93148811],
                          [  2.95859623,   1.60068655,  17.39446445],
                          [  3.63755131,   4.13458109,  13.7       ],
                          [  3.63755131,   4.13458109,  16.16297622],
                          [  3.63755131,   4.13458109,  18.62595243],
                          [  1.78261185,   3.63755131,  14.93148811],
                          [  1.78261185,   3.63755131,  17.39446445],
                          [  2.27964163,   1.78261185,  13.7       ],
                          [  2.27964163,   1.78261185,  16.16297622],
                          [  2.27964163,   1.78261185,  18.62595243],
                          [  4.13458109,   2.27964163,  14.93148811],
                          [  4.13458109,   2.27964163,  17.39446445],
                          [  2.77468705,   2.77468705,  11.77200005],
                          [  2.77468705,   2.77468705,  20.59799979],
                          [  4.1620307 ,   1.38734353,  22.56000056],
                          [  4.1620307 ,   4.1620307 ,  22.56000056],
                          [  1.38734353,   1.38734353,  22.56000056],
                          [  1.38734353,   4.1620307 ,  22.56000056]]*Angstrom
       

electrode_elements = [Platinum, Platinum, Platinum, Platinum]
electrode_coordinates = [[ 0.       ,  0.       ,  0.       ],
                         [ 1.3873435,  1.3873435,  1.962    ],
                         [ 0.       ,  0.       ,  3.924    ],
                         [ 1.3873435,  1.3873435,  5.886    ]]*Angstrom

electrode_cell = [[ 2.77468701,  0.        ,  0.        ],
                  [ 0.        ,  2.77468701,  0.        ],
                  [ 0.        ,  0.        ,  7.848     ]]*Angstrom

# Set up electrodes
electrode_configuration = PeriodicAtomConfiguration(
    electrode_cell,
    electrode_elements,
    electrode_coordinates
    )

# Set up two-probe configuration
twoprobe_configuration = TwoProbeConfiguration(
    (electrode_configuration,electrode_configuration),
    scattering_elements,
    scattering_coordinates,
    electrode_repetitions=[[2,2],[2,2]],
    equivalent_atoms=([0,0],[3,30])
    )
if processIsMaster(): nlPrint(twoprobe_configuration)
if processIsMaster(): file.addToSample(twoprobe_configuration, 'twoprobe_configuration')

######################################################################
# Central region parameters
######################################################################
exchange_correlation_type = LDA.PZ

iteration_mixing_parameters = iterationMixingParameters(
    algorithm = IterationMixing.Pulay,
    diagonal_mixing_parameter = 0.05,
    quantity = IterationMixing.Hamiltonian,
    history_steps = 6
)

electron_density_parameters = electronDensityParameters(
    mesh_cutoff = 200.0*Rydberg
)

basis_set_parameters = basisSetParameters(
    type = DoubleZetaPolarized,
    radial_sampling_dr = 0.001*Bohr,
    energy_shift = 0.01*Rydberg,
    delta_rinn = 0.8,
    v0 = 40.0*Rydberg,
    charge = 0.0,
    split_norm = 0.15
)

iteration_control_parameters = iterationControlParameters(
    tolerance = 1e-005,
    criterion = IterationControl.TotalEnergy,
    max_steps = 110
)

electrode_voltages = (-0.1,0.1)*Volt

two_probe_algorithm_parameters = twoProbeAlgorithmParameters(
    electrode_constraint = ElectrodeConstraints.Off,
    initial_density_type = InitialDensityType.EquivalentBulk
)

energy_contour_integral_parameters = energyContourIntegralParameters(
    circle_points = 30,
    integral_lower_bound = 3.0*Rydberg,
    fermi_line_points = 10,
    fermi_function_poles = 4,
    real_axis_infinitesimal = 0.01*electronVolt,
    real_axis_point_density = 0.02*electronVolt
)

two_center_integral_parameters = twoCenterIntegralParameters(
    cutoff = 2500.0*Rydberg,
    points = 1024
)

######################################################################
# Left electrode parameters
######################################################################
left_electrode_electron_density_parameters = electronDensityParameters(
    mesh_cutoff = 200.0*Rydberg
)

left_electrode_iteration_control_parameters = iterationControlParameters(
    tolerance = 1e-005,
    criterion = IterationControl.TotalEnergy,
    max_steps = 110
)

left_electrode_brillouin_zone_integration_parameters = brillouinZoneIntegrationParameters(
    monkhorst_pack_parameters = (5, 5, 500)
)

left_electrode_iteration_mixing_parameters = iterationMixingParameters(
    algorithm = IterationMixing.Pulay,
    diagonal_mixing_parameter = 0.05,
    quantity = IterationMixing.Hamiltonian,
    history_steps = 6
)

left_electrode_eigenstate_occupation_parameters = eigenstateOccupationParameters(
    temperature = 2000.0*Kelvin
)

######################################################################
# Collect left electrode parameters
######################################################################
left_electrode_parameters = ElectrodeParameters(
    brillouin_zone_integration_parameters = left_electrode_brillouin_zone_integration_parameters,
    electron_density_parameters = left_electrode_electron_density_parameters,
    eigenstate_occupation_parameters = left_electrode_eigenstate_occupation_parameters,
    iteration_mixing_parameters = left_electrode_iteration_mixing_parameters,
    iteration_control_parameters = left_electrode_iteration_control_parameters
)

######################################################################
# Right electrode parameters
######################################################################
right_electrode_electron_density_parameters = electronDensityParameters(
    mesh_cutoff = 200.0*Rydberg
)

right_electrode_iteration_control_parameters = iterationControlParameters(
    tolerance = 1e-005,
    criterion = IterationControl.TotalEnergy,
    max_steps = 110
)

right_electrode_brillouin_zone_integration_parameters = brillouinZoneIntegrationParameters(
    monkhorst_pack_parameters = (5, 5, 500)
)

right_electrode_iteration_mixing_parameters = iterationMixingParameters(
    algorithm = IterationMixing.Pulay,
    diagonal_mixing_parameter = 0.05,
    quantity = IterationMixing.Hamiltonian,
    history_steps = 6
)

right_electrode_eigenstate_occupation_parameters = eigenstateOccupationParameters(
    temperature = 2000.0*Kelvin
)

######################################################################
# Collect right electrode parameters
######################################################################
right_electrode_parameters = ElectrodeParameters(
    brillouin_zone_integration_parameters = right_electrode_brillouin_zone_integration_parameters,
    electron_density_parameters = right_electrode_electron_density_parameters,
    eigenstate_occupation_parameters = right_electrode_eigenstate_occupation_parameters,
    iteration_mixing_parameters = right_electrode_iteration_mixing_parameters,
    iteration_control_parameters = right_electrode_iteration_control_parameters
)

######################################################################
# Initialize self-consistent field calculation
######################################################################
two_probe_method = TwoProbeMethod(
    electrode_parameters = (left_electrode_parameters,right_electrode_parameters),
    exchange_correlation_type = exchange_correlation_type,
    iteration_mixing_parameters = iteration_mixing_parameters,
    electron_density_parameters = electron_density_parameters,
    basis_set_parameters = basis_set_parameters,
    iteration_control_parameters = iteration_control_parameters,
    energy_contour_integral_parameters = energy_contour_integral_parameters,
    two_center_integral_parameters = two_center_integral_parameters,
    electrode_voltages = electrode_voltages,
    algorithm_parameters = two_probe_algorithm_parameters
)
if processIsMaster(): nlPrint(two_probe_method)

runtime_parameters = runtimeParameters(
    verbosity_level = 10,
    checkpoint_filename = 'C:/Users/Nano/Desktop/apt chrismas/apt1.nc'
)

# Perform self-consistent field calculation
scf = executeSelfConsistentCalculation(
    twoprobe_configuration,
    two_probe_method,
    runtime_parameters = runtime_parameters
)

######################################################################
# Calculate physical properties
######################################################################
current = calculateCurrent(
    self_consistent_calculation = scf,
    brillouin_zone_integration_parameters = brillouinZoneIntegrationParameters((1, 1)),
    green_function_infinitesimal = 1.0e-5*electronVolt,
    number_of_points = 100
)
if processIsMaster(): nlPrint(current)
if processIsMaster(): file.addToSample(current, 'twoprobe_configuration', 'Current')

local_density_of_states = calculateLocalDensityOfStates(
    self_consistent_calculation = scf,
    energy = 0.0*electronVolt,
    quantum_number = (0.0,0.0),
    green_function_infinitesimal = 1.0e-5*electronVolt
)
if processIsMaster(): file.addToSample(local_density_of_states, 'twoprobe_configuration', 'Local Density Of States')

transmission_coefficients = calculateTransmissionCoefficients(
    self_consistent_calculation = scf,
    energy = 0.0*electronVolt,
    quantum_numbers = ((0.0,0.0),(0.5,0.5)),
    green_function_infinitesimal = 1.0e-5*electronVolt
)
if processIsMaster(): nlPrint(transmission_coefficients)
if processIsMaster(): file.addToSample(transmission_coefficients, 'twoprobe_configuration', 'Transmission Coefficients')

transmission_spectrum = calculateTransmissionSpectrum(
    self_consistent_calculation = scf,
    energies = (0.0,)*electronVolt,
    brillouin_zone_integration_parameters = brillouinZoneIntegrationParameters((1, 1)),
    green_function_infinitesimal = 1.0e-5*electronVolt
)
if processIsMaster(): nlPrint(transmission_spectrum)
if processIsMaster(): file.addToSample(transmission_spectrum, 'twoprobe_configuration', 'Transmission Spectrum')

mulliken_population = calculateMullikenPopulation(self_consistent_calculation = scf)
if processIsMaster(): nlPrint(mulliken_population)
if processIsMaster(): file.addToSample(mulliken_population, 'twoprobe_configuration', 'Mulliken Population')

electron_density = calculateElectronDensity(self_consistent_calculation = scf)
if processIsMaster(): file.addToSample(electron_density, 'twoprobe_configuration', 'Electron Density')

transmission_eigenstates = calculateTransmissionEigenstates(
    self_consistent_calculation = scf,
    energy = 0.0*electronVolt,
    quantum_numbers = (0,((0.0,0.0),(0.5,0.5)))
)
for state_index,state in enumerate(transmission_eigenstates):
    label='Transmission Eigenstates'+' '+str(state_index)
    if processIsMaster(): file.addToSample(state, 'twoprobe_configuration', label)

transmission_eigenvalues = calculateTransmissionEigenvalues(
    self_consistent_calculation = scf,
    energy = 0.0*electronVolt,
    quantum_numbers = ((0.0,0.0),(0.5,0.5))
)
if processIsMaster(): nlPrint(transmission_eigenvalues)
for value_index,transmission_eigenvalue in enumerate(transmission_eigenvalues):
    label='Transmission Eigenvalues'+' '+str(value_index)
    if processIsMaster(): file.addToSample(transmission_eigenvalue, 'twoprobe_configuration', label)

9

General Questions and Answers / Re: Transmission Spectrum Error

« on: December 16, 2010, 16:20 »

The message shows that the iteration steps exceed the specified one. To solve the problem, at least you may try to increase the maximum iteration step. Regarding to the setup of configuration defined in your script file, there are some other reasons for the bad convergence problem in your calculation:
i) Since the electrode consists of bulk Pt, the k-mesh in the x and y direction (i.e., 2x2x..) may not sufficient. It should be increased further.
ii) In the scattering region, the atomic layers of Pt are used as surface layers actually, and the atomic layers of carbon act as the conductor in a two-probe system. Moreover, the atomic layers of carbon seem to be cleaved from an artificial structure of carbon, rather than from graphite, diamond, graphene, or atomic chain. The atomic configuration of your two-probe system needs to checked, i.e., what kind of structure do you really to calculate in your study?
iii) For the Pt, the szp basis set may be insufficient.

Please tell me how to decide k-mesh values in the x,y,z directions, and why the szp basis set is insufficient ?

10

General Questions and Answers / Exceeded maximum number of self-consistent iterations

« on: December 16, 2010, 07:57 »

Hi
   Why following error occurs when i try to obtain transmission spectrum
---------
  Traceback (most recent call last):
  File "c:/users/nano/appdata/local/temp/tmpf_6irn.nl", line 419, in ?
    runtime_parameters = runtime_parameters
ATKError: Exceeded maximum number of self-consistent iterations.
Terminated Abnormally

11

General Questions and Answers / Transmission Spectrum Error

« on: December 15, 2010, 09:51 »

Dear all
    I have atk+vnl version 2008.10
    When I try to calculate transmission spectrum than following error appears:


Traceback (most recent call last):
  File "c:/users/nano/appdata/local/temp/tmpf_6irn.nl", line 419, in ?
    runtime_parameters = runtime_parameters
ATKError: Exceeded maximum number of self-consistent iterations.
Terminated Abnormally



My script is following

from ATK.TwoProbe import *
from ATK.MPI import processIsMaster

# Generate time stamp
if processIsMaster():
    import platform, time
    print '#',time.ctime()
    print '#',platform.node(),platform.platform()+'\n'

# Opening vnlfile
if processIsMaster(): file = VNLFile('C:/Users/Nano/Desktop/Abshiek_Pt_Project/apt2.vnl')

# Scattering elements and coordinates
scattering_elements = [Platinum, Platinum, Platinum, Carbon,   
                       Carbon,   Platinum, Platinum]
scattering_coordinates = [[  0.00000000e+00,   0.00000000e+00,   7.84800005e+00],
                          [  1.38734353e+00,   1.38734353e+00,   9.81000042e+00],
                          [  0.00000000e+00,   0.00000000e+00,   1.17720003e+01],
                          [ -2.77555756e-17,  -4.68440608e-17,   1.37299532e+01],
                          [  2.77555756e-17,   4.68440608e-17,   1.52600468e+01],
                          [  0.00000000e+00,   0.00000000e+00,   1.72219995e+01],
                          [  1.38734353e+00,   1.38734353e+00,   1.91839996e+01]]*Angstrom
       

electrode_elements = [Platinum, Platinum, Platinum, Platinum]
electrode_coordinates = [[ 0.       ,  0.       ,  0.       ],
                         [ 1.3873435,  1.3873435,  1.962    ],
                         [ 0.       ,  0.       ,  3.924    ],
                         [ 1.3873435,  1.3873435,  5.886    ]]*Angstrom

electrode_cell = [[ 2.77468701,  0.        ,  0.        ],
                  [ 0.        ,  2.77468701,  0.        ],
                  [ 0.        ,  0.        ,  7.848     ]]*Angstrom

# Set up electrodes
electrode_configuration = PeriodicAtomConfiguration(
    electrode_cell,
    electrode_elements,
    electrode_coordinates
    )

# Set up two-probe configuration
twoprobe_configuration = TwoProbeConfiguration(
    (electrode_configuration,electrode_configuration),
    scattering_elements,
    scattering_coordinates,
    electrode_repetitions=[[1,1],[1,1]],
    equivalent_atoms=([0,0],[3,6])
    )
if processIsMaster(): nlPrint(twoprobe_configuration)
if processIsMaster(): file.addToSample(twoprobe_configuration, 'twoprobe_configuration')

######################################################################
# Central region parameters
######################################################################
exchange_correlation_type = LDA.PZ

iteration_mixing_parameters = iterationMixingParameters(
    algorithm = IterationMixing.Pulay,
    diagonal_mixing_parameter = 0.05,
    quantity = IterationMixing.Hamiltonian,
    history_steps = 6
)

electron_density_parameters = electronDensityParameters(
    mesh_cutoff = 200.0*Rydberg
)

basis_set_parameters = basisSetParameters(
    type = SingleZetaPolarized,
    radial_sampling_dr = 0.001*Bohr,
    energy_shift = 0.01*Rydberg,
    delta_rinn = 0.8,
    v0 = 40.0*Rydberg,
    charge = 0.0,
    split_norm = 0.15
)

iteration_control_parameters = iterationControlParameters(
    tolerance = 1e-005,
    criterion = IterationControl.TotalEnergy,
    max_steps = 100
)

electrode_voltages = (-0.1,0.1)*Volt

two_probe_algorithm_parameters = twoProbeAlgorithmParameters(
    electrode_constraint = ElectrodeConstraints.Off,
    initial_density_type = InitialDensityType.EquivalentBulk
)

energy_contour_integral_parameters = energyContourIntegralParameters(
    circle_points = 30,
    integral_lower_bound = 3*Rydberg,
    fermi_line_points = 10,
    fermi_function_poles = 4,
    real_axis_infinitesimal = 0.01*electronVolt,
    real_axis_point_density = 0.02*electronVolt
)

two_center_integral_parameters = twoCenterIntegralParameters(
    cutoff = 2500.0*Rydberg,
    points = 1024
)

######################################################################
# Left electrode parameters
######################################################################
left_electrode_electron_density_parameters = electronDensityParameters(
    mesh_cutoff = 200.0*Rydberg
)

left_electrode_iteration_control_parameters = iterationControlParameters(
    tolerance = 1e-005,
    criterion = IterationControl.TotalEnergy,
    max_steps = 100
)

left_electrode_brillouin_zone_integration_parameters = brillouinZoneIntegrationParameters(
    monkhorst_pack_parameters = (2, 2, 100)
)

left_electrode_iteration_mixing_parameters = iterationMixingParameters(
    algorithm = IterationMixing.Pulay,
    diagonal_mixing_parameter = 0.05,
    quantity = IterationMixing.Hamiltonian,
    history_steps = 6
)

left_electrode_eigenstate_occupation_parameters = eigenstateOccupationParameters(
    temperature = 1000.0*Kelvin
)

######################################################################
# Collect left electrode parameters
######################################################################
left_electrode_parameters = ElectrodeParameters(
    brillouin_zone_integration_parameters = left_electrode_brillouin_zone_integration_parameters,
    electron_density_parameters = left_electrode_electron_density_parameters,
    eigenstate_occupation_parameters = left_electrode_eigenstate_occupation_parameters,
    iteration_mixing_parameters = left_electrode_iteration_mixing_parameters,
    iteration_control_parameters = left_electrode_iteration_control_parameters
)

######################################################################
# Right electrode parameters
######################################################################
right_electrode_electron_density_parameters = electronDensityParameters(
    mesh_cutoff = 200.0*Rydberg
)

right_electrode_iteration_control_parameters = iterationControlParameters(
    tolerance = 1e-005,
    criterion = IterationControl.TotalEnergy,
    max_steps = 100
)

right_electrode_brillouin_zone_integration_parameters = brillouinZoneIntegrationParameters(
    monkhorst_pack_parameters = (2, 2, 100)
)

right_electrode_iteration_mixing_parameters = iterationMixingParameters(
    algorithm = IterationMixing.Pulay,
    diagonal_mixing_parameter = 0.05,
    quantity = IterationMixing.Hamiltonian,
    history_steps = 6
)

right_electrode_eigenstate_occupation_parameters = eigenstateOccupationParameters(
    temperature = 1000.0*Kelvin
)

######################################################################
# Collect right electrode parameters
######################################################################
right_electrode_parameters = ElectrodeParameters(
    brillouin_zone_integration_parameters = right_electrode_brillouin_zone_integration_parameters,
    electron_density_parameters = right_electrode_electron_density_parameters,
    eigenstate_occupation_parameters = right_electrode_eigenstate_occupation_parameters,
    iteration_mixing_parameters = right_electrode_iteration_mixing_parameters,
    iteration_control_parameters = right_electrode_iteration_control_parameters
)

######################################################################
# Initialize self-consistent field calculation
######################################################################
two_probe_method = TwoProbeMethod(
    electrode_parameters = (left_electrode_parameters,right_electrode_parameters),
    exchange_correlation_type = exchange_correlation_type,
    iteration_mixing_parameters = iteration_mixing_parameters,
    electron_density_parameters = electron_density_parameters,
    basis_set_parameters = basis_set_parameters,
    iteration_control_parameters = iteration_control_parameters,
    energy_contour_integral_parameters = energy_contour_integral_parameters,
    two_center_integral_parameters = two_center_integral_parameters,
    electrode_voltages = electrode_voltages,
    algorithm_parameters = two_probe_algorithm_parameters
)
if processIsMaster(): nlPrint(two_probe_method)

runtime_parameters = runtimeParameters(
    verbosity_level = 10,
    checkpoint_filename = 'C:/Users/Nano/Desktop/Abshiek_Pt_Project/apt2.nc'
)

# Perform self-consistent field calculation
scf = executeSelfConsistentCalculation(
    twoprobe_configuration,
    two_probe_method,
    runtime_parameters = runtime_parameters
)

######################################################################
# Calculate physical properties
######################################################################
transmission_spectrum = calculateTransmissionSpectrum(
    self_consistent_calculation = scf,
    energies = (0.0,)*electronVolt,
    brillouin_zone_integration_parameters = brillouinZoneIntegrationParameters((1, 1)),
    green_function_infinitesimal = 1.0e-5*electronVolt
)
if processIsMaster(): nlPrint(transmission_spectrum)
if processIsMaster(): file.addToSample(transmission_spectrum, 'twoprobe_configuration', 'Transmission Spectrum')

current = calculateCurrent(
    self_consistent_calculation = scf,
    brillouin_zone_integration_parameters = brillouinZoneIntegrationParameters((1, 1)),
    green_function_infinitesimal = 1.0e-5*electronVolt,
    number_of_points = 100
)
if processIsMaster(): nlPrint(current)
if processIsMaster(): file.addToSample(current, 'twoprobe_configuration', 'Current')

# Set verbosity level so that all energy components are printed
import ATK
verbosity_level=ATK.verbosityLevel()
ATK.setVerbosityLevel(10)
total_energy = calculateTotalEnergy(self_consistent_calculation = scf)
ATK.setVerbosityLevel(verbosity_level)

if processIsMaster(): nlPrint(total_energy,'Total energy')
if processIsMaster(): file.addToSample(total_energy, 'twoprobe_configuration', 'Total energy')

transmission_eigenstates = calculateTransmissionEigenstates(
    self_consistent_calculation = scf,
    energy = 0.0*electronVolt,
    quantum_numbers = (0,((0.0,0.0),(0.5,0.5)))
)
for state_index,state in enumerate(transmission_eigenstates):
    label='Transmission Eigenstates'+' '+str(state_index)
    if processIsMaster(): file.addToSample(state, 'twoprobe_configuration', label)









help me to solve this error

 

12

General Questions and Answers / Help about basis set parameter

« on: July 28, 2010, 17:09 »

 Hello!
 

 I want to know in depth that what is exactly meaning and physical interpretation of different basis set and basis set parameters used in calculation. How i can know that particular basis set and basis set paremetesr are appropriate for calculation for given system. Please help me .