ShieldingTensors¶
- class ShieldingTensors(configuration, finite_difference_q=None)¶
Class for calculating and representing NMR shielding tensors using the Gauge Including Projector Augmentated Wave (GIPAW) method.
Warning
It does not work for metals, only semiconductors and insulators.
- Parameters:
configuration (
BulkConfiguration
) – Configuration with a calculator that supports GIPAW calculations.finite_difference_q (PhysicalQuantity) – The magnitude of the reciprocal space displacement to use when evaluating the finite difference q derivative in the GIPAW method. Must be a PhysicalQuantity of dimension inverse length. Default: 0.01 Bohr^(-1)
- components()¶
Get the components to the shielding tensors for all atoms.
- Returns:
A dictionary with the components of shielding tensors for the requested atoms.
- Return type:
dict
- evaluate()¶
Get the calculated total shielding tensors for all atoms.
- Returns:
A list of shielding tensors for the requested atoms.
- Return type:
list
- evaluateAnisotropicChemicalShielding()¶
Determine the anisotropic chemical shielding for each atom. Using Haeberlen convention:
sigma_anisotropy = sigma_{zz} - (sigma_{xx}+sigma_{yy})/2 = 3 * reduced_sigma_anisotropy / 2
Where:
|sigma_{zz}-sigma_iso| > |sigma_{yy}-sigma_iso| > |sigma_{xx}-sigma_iso|
- Returns:
The anisotropic chemical shielding for each atom.
- Return type:
list
- evaluateAsymmetryParameter()¶
Determine the asymmetry parameter for each atom. Using Haeberlen convention:
eta = (sigma_{xx} - sigma_{yy})/reduced_sigma_anisotropy
Where:
|sigma_{zz}-sigma_iso| > |sigma_{yy}-sigma_iso| > |sigma_{xx}-sigma_iso|
- Returns:
The asymmetry parameter for each atom.
- Return type:
list
- evaluateIsotropicChemicalShielding()¶
Determine the isotropic chemical shielding for each atom.
- Returns:
The isotropic chemical shielding for each atom.
- Return type:
list
- evaluatePrincipalAxis()¶
Determine the principel axis (eigenvectors and eigenvalues of the shielding tensor) for each atom. Using Haeberlen convention:
|sigma_{zz}-sigma_iso| > |sigma_{yy}-sigma_iso| > |sigma_{xx}-sigma_iso|
- Returns:
The principel axis for each atom.
- Return type:
two ndarray
- evaluateReducedAnisotropicChemicalShielding()¶
Determine the reduced anisotropic chemical shielding for each atom. Using Haeberlen convention: reduced_sigma_anisotropy = sigma_{zz} - sigma_iso
Where:
|sigma_{zz}-sigma_iso| > |sigma_{yy}-sigma_iso| > |sigma_{xx}-sigma_iso|
- Returns:
The anisotropic chemical shielding for each atom.
- Return type:
list
- evaluateSkew()¶
Determine the skew parameter for each atom. Using Herzfeld-Berger convention:
- Skew = 3*(sigma_{22} - sigma_{iso})/span (-1 =< Skew =< 1)
= 3*(sigma_{22} - sigma_{iso})/(sigma_{11} - sigma_{33})
Where: sigma_{11} > sigma_{22} > sigma_{33} (std. convention)
- Returns:
The span parameter for each atom.
- Return type:
list
- evaluateSpan()¶
Determine the span parameter for each atom. Using Herzfeld-Berger convention:
Span = (sigma_{11} - sigma_{33}) (Span >= 0)
Where: sigma_{11} > sigma_{22} > sigma_{33} (std. convention)
- Returns:
The span parameter for each atom.
- Return type:
list
- metatext()¶
- Returns:
The metatext of the object or None if no metatext is present.
- Return type:
str | None
- nlprint(stream=None)¶
Print a string containing an ASCII table useful for plotting the AnalysisSpin object.
- Parameters:
stream (python stream) – The stream the table should be written to. Default:
NLPrintLogger()
- setMetatext(metatext)¶
Set a given metatext string on the object.
- Parameters:
metatext (str | None) – The metatext string that should be set. A value of “None” can be given to remove the current metatext.
- uniqueString()¶
Return a unique string representing the state of the object.