Sample packing and spinning
While sample spinning stability with the facility's DOR probe is much improved on the current generation of DOR probes thanks to the computer-controlled spinning technology developed in Ago Samoson's laboratory in Tallinn, Estonia, the requirement for the centres of gravity of the separate inner and outer rotors to be exactly coincident means that DOR sample packing and spinning is still much more demanding as compared to MAS experiments.
To maximise the use of allocated 850 MHz spectrometer time, users are requested to send samples (a maximum of three) to the facility manager at least 1 week in advance, so that the facility manager can check the spinning performance. If you would like to request facility time for more than three samples in one visit, you should include time for repacking of samples: as a guideline, 3-4 hours should be reserved per sample. If your samples are not simple crystalline solids and do not spin easily under MAS, please discuss with the facility manager in advance of submitting your proposal, e.g., in the Warwick group's experience, glass and ceramic samples can be more tricky to get to spin in DOR.
probe tuning range
DOUBLE RESONANCE CONFIGURATION
1H Channel: Tuning Range 850 +/- 10 MHz (1H decoupling has been tested at a 1H nutation frequency of 26 kHz (-3.0 dB))
X Channel: Tuning Range 49-279 MHz
X Channel: Tuning range 42.3 – 282 MHz (for 23Na, a rf nutation frequency of 41 kHz (-2.5dB) has been tested)