SymmetricTensor¶

class mrsimulator.spin_system.tensors.SymmetricTensor(*, property_units: Dict = {'Cq': 'Hz', 'alpha': 'rad', 'beta': 'rad', 'gamma': 'rad', 'zeta': 'ppm'}, zeta: float = None, Cq: float = None, eta: mrsimulator.spin_system.tensors.ConstrainedFloatValue = None, alpha: float = None, beta: float = None, gamma: float = None)¶

Bases: mrsimulator.utils.parseable.Parseable

Base SymmetricTensor class representing the traceless symmetric part of an irreducible second-rank tensor.

zeta¶

The anisotropy parameter of the nuclear shielding tensor, in ppm, expressed using the Haeberlen convention. The default value is None.

Example

>>> shielding = SymmetricTensor()
>>> shielding.zeta = 10

Type: float (optional)

Cq¶

The quadrupolar coupling constant, in Hz, derived from the electric field gradient tensor. The default value is None.

Example

>>> efg = SymmetricTensor()
>>> efg.Cq = 10e6

Type: float (optional)

eta¶

The asymmetry parameter of the SymmetricTensor expressed using the Haeberlen convention. The default value is None.

Example

>>> shielding.eta = 0.1
>>> efg.eta = 0.5

Type: float (optional)

alpha¶

Euler angle, \(\alpha\), in radians. The default value is None.

Example

>>> shielding.alpha = 0.15
>>> efg.alpha = 1.5

Type: float (optional)

beta¶

Euler angle, \(\beta\), in radians. The default value is None.

Example

>>> shielding.beta = 3.1415
>>> efg.beta = 1.1451

Type: float (optional)

gamma¶

Euler angle, \(\gamma\), in radians. The default value is None.

Example

>>> shielding.gamma = 2.1
>>> efg.gamma = 0

Type: float (optional)

Example

>>> shielding = SymmetricTensor(zeta=10, eta=0.1, alpha=0.15, beta=3.14, gamma=2.1)
>>> efg = SymmetricTensor(Cq=10e6, eta=0.5, alpha=1.5, beta=1.1451, gamma=0)

Method Documentation

to_freq_dict(larmor_frequency: float) → dict¶

Serialize the SymmetricTensor object to a JSON compliant python dictionary where the attribute values are numbers expressed in default units. The default unit for attributes with respective dimensionalities are: - frequency: Hz - angle: rad

Parameters: larmor_frequency (float) – The larmor frequency in MHz.
Returns: A python dict

json() → dict¶: Parse the class object to a JSON compliant python dictionary object where the attribute value with physical quantity is expressed as a string with a number and a unit.