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Fokker-Planck single angle spinning context. Generates a Liouvillian superoperator and passes it on to the pulse sequence function, which should be supplied as a handle.




  pulse_sequence      - pulse sequence function handle. See the
                        experiments directory for the list of
                        pulse sequences that ship with Spinach.

  parameters.rate     - spinning rate in Hz. Positive numbers
                        for JEOL, negative for Varian and Bruker
                        due to different rotation directions.

  parameters.axis     - spinning axis, given as a normalized
                        3-element vector

  parameters.spins    - a cell array giving the spins that 
                        the pulse sequence involves, e.g. 

  parameters.offset   - a cell array giving transmitter off-
                        sets in Hz on each of the spins listed
                        in parameters.spins array

  parameters.max_rank - maximum harmonic rank to retain in
                        the solution (increase till conver-
                        gence is achieved, approximately
                        equal to the number of spinning si-
                        debands in the spectrum)

  parameters.rframes  - rotating frame specification, e.g.
                        {{'13C',2},{'14N,3}} requests second
                        order rotating frame transformation
                        with respect to carbon-13 and third
                        order rotating frame transformation
                        with respect to nitrogen-14. When
                        this option is used, the assumptions
                        on the respective spins should be
                        laboratory frame.

  parameters.grid     - spherical grid file name. See grids
                        directory in the kernel.

  parameters.sum_up   - when set to 1 (default), returns the
                        powder average. When set to 0, returns
                        individual answers for each point in 
                        the powder as a cell array.

  parameters.*       - additional subfields may be required by your
                       pulse sequence - check its documentation page 

  assumptions        -  context-specific assumptions ('nmr', 'epr',
                        'labframe', etc.) - see the pulse sequence
                        header for information on this setting.

The parameters structure is passed to the pulse sequence with the following additional parameters set:

  parameters.spc_dim  - matrix dimension for the spatial
                        dynamics subspace

  parameters.spn_dim  - matrix dimension for the spin 
                        dynamics subspace


This function returns the powder average of whatever it is that the pulse sequence returns.


The following example files in the Spinach example set make use of this context function:

kinetics/mas_exchange_1.m - chemical exchange unser magic angle spinning

nmr_overtone/mas_glycine_1.m - 14N MAS quadrupo9lar overtone spectrum

nmr_solids/mas_powder_gly_fplanck.m - glycine 13C MAS NMR spectrum

nmr_solids/mas_powder_dip_fplanck.m - MAS NMR on a pair of dipole coupled spins

nmr_solids/mas_powder_csa_fplanck.m - MAS NMR on a simple system with a CSA


  1. Arbitrary order rotating frame transformation is supported, including infinite order. See rotframe.m for further information.
  2. Use 'single_crystal' powder grid for single crystal simulations.
  3. The function supports parallel processing via Matlab's Distributed Computing Toolbox - different system orientations are evaluated on different labs.

See also

powder.m, liquid.m, roadmap.m, doublerot.m, crystal.m, imaging.m, gridfree.m, floquet.m

Version 2.2, authors: Ilya Kuprov