|nmrML location||nmrML param||Definition||Bruker||Varian||Jeol||Required Unit|
Required by Processing Tool
MASR is difficult, as is set to obscure values even with liquid NMR experiments e.g. 4300Hz). MASR may contain a dummy value set per default in th ecase when no MAS-apparatus is connected to the spectrometer.
Maybe remove this as needed flip angle is often not known? This seems to be the nutation frequency of a pulse. Computation via pulse length (p1) and flip angle of pulse. At 90°-Pulse we would have gamma*B1 = 1/(4*p1). Would be around kHz to 100kHz.
Rename NUC1 for Bruker
Replaces the hardPulse parameter. It should be automatically calculated from the pulse width in the procs file and the excitation angle. If you say the pulse width you also have to specify the excitation angle, so this way is more compact/useful. Should be recorded in Tesla, not in Hz.
Chr. Ludwig: I can't quite remember why that parameter was put into BML_NMR. I think it is the gamma B1 field strength. Therefore the field gamma_b1_pulse_field_strength can be removed. For a square pulse it can be simply computed from flip angle and pulse length. However for polychromatic pulses (as used in multi-solvent saturation and/or Hadamard-spectroscopy) and adiabatic pulses (e.g. used for optimal transfer in 2D-TOCSY spectra and also to optimise polarisation transfer in 1H,13C-HSQC spectra) the situation is a lot more complicated. In these cases there is still a relationship between pulse length/flip angle and either the maximal gamma B1 field strength or the average field strength, but additional parameters can influence this as well. Therefore it becomes an independent parameter in its own right. I think we decided on something like the effectiveExcitationField to keep things simple and as independent of the specific pulse sequence details as possible.The simplest way to retrieve this parameter is to refer to the maximum
B1 field strength of the pulse. This is encoded in the power level and
can be derived from a comparison of the pulses power level to the
corresponding B1 field strength and power level of a square pulse (there
is usually one square excitation pulses executed for each channel (i.e.
nucleus) used in the pulse sequence.The unit should be Hz, not megaHertz or Tesla. Hz is the commonly used
unit to express the field strength of NMR pulses. Bruker data sets store
this information in pldb? or plw?, where the question mark replaces a
number (0...63) and where db refers to a logarithmic scale and w to a
scale in watts. I can't remember what the varian equivalents are, but
they are usually user defined entries, i.e. not really standadised.
DJ: I am totally confused too by now :-( DS: So this is computed... but from exact what Bruker and Varian Parameters ? There are no pulse length and excitation breath to be found in the proc file. If no one uses it, delete this element ?) Was this needed by C Ludwig of BML ? Its definition hints for B1-Fieldstrength.
hertz (also available in ppm as sw for bruker)
Rename Bruker parameter to SW_h ? Bruker computes via BF1, as at acquisition time SF is not yet known.
Rename NUC2 for Bruker
What is meant here ? The sampling in the direct dimensions for nD-Experiments? E.g. TPPI, States, etc.?
The absolute frequency (MHz) of the reference substance (e.g. TMS at 1H). Can be interpreted as Larmorfrequency. In Bruker SF = BF1 + SR
Maybe this LamorFrequency would match our effectiveExcitationField ?
|Further Parameters as required by processiong tools (only add if less than 5 required)|