Psyche.m

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PSYCHE pure-shift NMR pulse sequence.

Syntax

       fid=psyche(spin_system,parameters,H,R,K,G,F)

Arguments

parameters.rho0           initial state

parameters.coil           detection state

parameters.spins          nuclei on which the sequence runs

parameters.g_amp          gradient amplitude (T/m)

parameters.dims           size of the sample (m)

parameters.npts           number of discretization points in the grid

parameters.npoints        two-element point count array for the two
                         evolution dimensions

parameters.diff           diffusion constant (m^2/s)

parameters.pulsenpoints   number of points in the chirp pulse waveform

parameters.duration       chirp pulse duration, seconds

parameters.bandwidth      chirp pulse bandwidth, Hz

parameters.smfactor       chirp smoothing factor

parameters.chirptype      chirp pulse type: 'wurst', 'wurst-adaptive',
                         'smoothed', 'smoothed-adaptive', 'saltire',
                         or 'saltire-adaptive'

parameters.beta           chirp pulse flip angle, degrees

parameters.timestep1      first evolution timestep, seconds

parameters.timestep2      second evolution timestep, seconds

parameters.delta          diffusion delay, seconds

H                         Fokker-Planck Hamiltonian

R                         Fokker-Planck relaxation superoperator

K                         Fokker-Planck kinetics superoperator

G                         Fokker-Planck gradient superoperators

F                         Fokker-Planck diffusion and flow superoperator

Outputs

fid - a PSYCHE free induction decay as a 2D array

Notes

The last five parameters are built automatically by imaging.m context function when this sequence is called from that context.

See also

step.m, evolution.m, coherence.m, chirp_pulse.m, shaped_pulse_xy.m

Shaped pulses and gradients

Version 1.10, authors: Mohammadali Foroozandeh, Maria Grazia Concilio