Subsections


model_free.create_model

Image model-free Image list-add-relax-blue

Synopsis

Create a model-free model.

Defaults

model_free.create_model(model=None, equation=None, params=None, spin_id=None)

Keyword arguments

model: The new name of the model-free model.

equation: The model-free equation.

params: The array of parameter names of the model.

spin_id: The spin identification string.

Description

This user function should almost never be used. It is provided for academic reasons for the study of old analyses and published results. If you are looking for a normal model-free model, use the model_free.select_model user function instead.

Model-free equation

The model-free equation can be one of the following:

`mf_orig' selects the original model-free equations with parameters {S2, τe}.
`mf_ext' selects the extended model-free equations with parameters {S2f, τf, S2, τs}.
`mf_ext2' selects the extended model-free equations with parameters {S2f, τf, S2s, τs}.

Model-free parameters

The following parameters are accepted for the original model-free equation:

`s2' -
The square of the generalised order parameter.
`te' -
The effective correlation time.

The following parameters are accepted for the extended model-free equation:

`s2f' -
The square of the generalised order parameter of the faster motion.
`tf' -
The effective correlation time of the faster motion.
`s2' -
The square of the generalised order parameter S2 = S2f * S2s.
`ts' -
The effective correlation time of the slower motion.

The following parameters are accepted for the extended 2 model-free equation:

`s2f' -
The square of the generalised order parameter of the faster motion.
`tf' -
The effective correlation time of the faster motion.
`s2s' -
The square of the generalised order parameter of the slower motion.
`ts' -
The effective correlation time of the slower motion.

The following parameters are accepted for all equations:

`rex' -
The chemical exchange relaxation.
`r' -
The average bond length <r>.
`csa' -
The chemical shift anisotropy.

Spin identification string

If `spin_id' is supplied then the model will only be created for the corresponding spins. Otherwise the model will be created for all spins.

Prompt examples

The following commands will create the model-free model `m1' which is based on the original model-free equation and contains the single parameter `s2'.

[numbers=none]
relax> model_free.create_model('m1', 'mf_orig', ['s2'])

[numbers=none]
relax> model_free.create_model(model='m1', params=['s2'], equation='mf_orig')

The following commands will create the model-free model `large_model' which is based on the extended model-free equation and contains the seven parameters `s2f', `tf', `s2', `ts', `rex', `csa', `r'.

[numbers=none]
relax> model_free.create_model('large_model', 'mf_ext', ['s2f', 'tf', 's2', 'ts', 'rex', 'csa', 'r'])

[numbers=none]
relax> model_free.create_model(model='large_model', params=['s2f', 'tf', 's2', 'ts', 'rex', 'csa', 'r'], equation='mf_ext')


The relax user manual (PDF), created 2016-10-28.