# Hnco.m

From Spinach Documentation Wiki

Phase-sensitive HNCO pulse sequence from

http://dx.doi.org/10.1016/0022-2364(90)90333-5

using the bidirectional propagation method described in

http://dx.doi.org/10.1016/j.jmr.2014.04.002

The sequence is hard-wired to work on 1H,13C,15N proteins. Syntax:

fid=hnco(spin_system,parameters,H,R,K)

where H is the hamiltonian commutation superoperator, R is the re- relaxation superoperator and K is the chemical kinetics superope- rator. The following parameters are required:

parameters.npoints - a vector of three integers giving the number of points in the three temporal dimensions, ordered as [t1 t2 t3].

parameters.sweep - a vector of three real numbers giving the sweep widths in the three frequen- cy dimensions, ordered as [f1 f2 f3].

parameters.tau - the three delays required for the ope- ration of the sequence (see the paper) in seconds. Reasonable values are [2.25e-3, 14e-3, 4e-3]

parameters.f1_decouple - logical switch controlling proton de- coupling during the T1 period.

Dimensions: F1 is N, F2 is CO, F3 is H.

Note: spin labels must be set to PDB atom IDs ('CA', 'HA', etc.) in sys.labels for this sequence to work properly.