Hi,
For the T1(R1), T2 (R2), and T1rho (R1rho) relaxation data a tag has
been available in the NMR-STAR dictionary for defining the 'coherence
type' that was observed in collecting the data. It has been pointed out
that the enumerated values for the coherence type tags were not
accurate. The existing enumerations include atom types (N, H, etc.),
information repeated in some sense in the data tables where the atoms
involved in the relaxation are listed.
In trying to improve how these data are represented, we have consulted
with people in the NMR facility here and have derived the draft proposal
shown below and would like to have feed back from you and those working
on the Relax project.
In this proposal, I and S are used as the general terms for the spins
involved. 'z' and '+' and '-' are used to describe the magnetization. In
addition to the tables for T1, T2, and T1rho, a new saveframe
(general_relaxation) has been added to capture relaxation data that may
not fit in the other categories. If a better term than
'general_relaxation' would fit these kinds of data, please provide your
advice.
Your comments and suggestions would be very helpful.
Thank you,
Eldon
save__Heteronucl_T1_list.T1_coherence_type
loop_
_item_enumeration_value
_item_enumeration_description
Iz 'zero quantum, longitudinal'
Sz 'zero quantum, longitudinal'
stop_
save_
save__Heteronucl_T1rho_list.T1rho_coherence_type
loop_
_item_enumeration_value
_item_enumeration_description
I(+,-) 'single quantum'
S(+,-) 'single quantum'
stop_
save_
save__Heteronucl_T2_list.T2_coherence_type
loop_
_item_enumeration_value
_item_enumeration_description
I(+,-) 'single quantum'
S(+,-) 'single quantum'
stop_
save_
save__General_relaxation_list.Relaxation_coherence_type
loop_
_item_enumeration_value
_item_enumeration_description
I(+,-)S(-,+) 'zero quantum'
IzSz 'zero quantum, longitudinal spin order'
I(+,-)Sz 'single quantum, antiphase'
IzS(+,-) 'single quantum, antiphase'
I(+,-)S(+,-) 'double quantum'
stop_
save_