COMPOZER-CP

[pessm...@gmail.com]

Dear Mikhail and all,

I am trying to simulate a 1H - 13C COMPOZER-CP experiment (cf. Fukuchi
et al. Efficient Cross-Polarization Using a Composite Zero Degree
Pulse for NMR Studies on Static Solids. J. Magn. Reson., 196, 105-109,
2009) with TPPM decoupling on the proton channel during acquisition.
The pulse sequence I simulated consists of synchronous X, -X, Y, and
then -Y 360 degree pulses on the proton and carbon channels (followed
by a 90 degree pulse on the carbon channel to observe). The effect of
these pulses should be to cause the less sensitive carbon nucleus's
magnetization to grow along the z-axis (like the experimentally
observed result).

I have not been able to produce results similar to the experimental
results of the COMPOZER-CP paper with SPINEVOLUTION. The carbon z-axis
magnetization doesn't grow as expected (it decays). Therefore I'm
wondering about the Hamiltonians. Is it possible to guide
SPINEVOLUTION to use a different Hamiltonian in this case? Or am I
completely on the wrong track? Simulating COMPOZER-CP as a zero
dimensional experiment with the observe every step option (and
observing carbon z-magnetization) produces essentially the same
results.

Please find the SPINEVOLUTION simulation below:

****** The System *******
spectrometer(MHz) 300
spinning_freq(kHz) 0.0
channels C13 H1
nuclei C13 H1 H1
atomic_coords CPZ_tppm.cor
cs_isotropic 4 0 2 ppm
csa_parameters 1 2.25 2.25 0 0 0 ppm
csa_parameters 2 4.9 0 0 0 0 ppm
csa_parameters 3 4.9 0 0 0 0 ppm
j_coupling *
quadrupole *
dip_switchboard *
csa_switchboard *
exchange_nuclei *
bond_len_nuclei *
bond_ang_nuclei *
tors_ang_nuclei *
groups_nuclei *
******* Pulse Sequence
***********************************************************************
CHN 1
timing(usec) [0.5 16 0.5 16 0.5 16 0.5 16]15 4
(100)2048
power(kHz) [0 62.5 0 62.5 0 62.5 0 62.5]15 62.5
0
phase(deg) [0 0 0 180 0 90 0 270]15
90 0
freq_offs(kHz) [0 0 0 0 0 0 0 0]15
0 0
CHN 2
timing(usec) [0.5 16 0.5 16 0.5 16 0.5 16]15 4
([1 1]50)
power(kHz) [0 62.5 0 62.5 0 62.5 0 62.5]15 0
[250 250]50
phase(deg) [0 0 0 180 0 90 0 270]15 0 [0
15]50
freq_offs(kHz) [0 0 0 0 0 0 0 0]15
0 [0]100
******* Variables
***************************************************************************
******* Options
*****************************************************************************
rho0 I1z+I2z
observables I1p
EulerAngles asg9045o
n_gamma *
line_broaden(Hz) 25
zerofill *
FFT_dimensions 1 ppm
options -re -t0



Thank you in advance,

Pieter Smith

[pessm...@gmail.com]

Reformatted SPINEVOLUTION file:

On Feb 4, 6:51 pm, "pessmit...@gmail.com" <pessmit...@gmail.com>
wrote:

[Mikhail Veshtort]

Dear Pieter,

I suggest that you play with the following input file first. It does
show build-up of Iz magnetization on the C13 nucleus. The build-up is
rather weak though.

Mikhail

****** The System ***********************************

spectrometer(MHz) 300
spinning_freq(kHz) 0.0
channels C13 H1
nuclei C13 H1 H1

atomic_coords ch2.cor
cs_isotropic *
csa_parameters *

j_coupling *
quadrupole *
dip_switchboard *
csa_switchboard *
exchange_nuclei *
bond_len_nuclei *
bond_ang_nuclei *
tors_ang_nuclei *
groups_nuclei *
******* Pulse Sequence ******************************

CHN 1
timing(usec) (16 16 16 16)16
power(kHz) 62.5 62.5 62.5 62.5
phase(deg) 0 180 90 270

freq_offs(kHz) 0 0 0 0

CHN 2
timing(usec) 16 16 16 16
power(kHz) 62.5 62.5 62.5 62.5
phase(deg) 0 180 90 270

freq_offs(kHz) 0 0 0 0

******* Variables ***************************************
******* Options etc *************************************
rho0 F2z
observables I1z F2z
EulerAngles rep168
n_gamma *
line_broaden(Hz) *
zerofill *
FFT_dimensions *
options *