Rey, our 700 MHz instrument has a dual configuration. It can be used as solution NMR instrument with a cryoprobe or it can be used as a solid-state NMR instrument. Changing the cryoprobe to conduct solid-state NMR experiments involves the following:
Pushing the “warm-up” button. This will start the automatic warm up procedure, which will take several hours. After this a lot of cables and hoses need to be disassembled. Pulling out the heavy cryoprobe takes two persons. One has to take great care to only hold the probe at its base to avoid damage. The cryoprobe has to be safely tucked away. Then the solid-state MAS probe can be installed, which involves deactivating the sample-changer, hooking tubes for the MAS pneumatic and connecting a bunch of cables. Once this is done a few calibration have to be performed or at least checked: the shim, the magic angle, power levels. A few glitches are to be expected – on Monday it took us ~4 hours to get the instrument ready, this is not counting the time it took the probe to warm up.
Reinstalling the cryoprobe is a similar effort. It is even worse – some of the connectors are really finnicky. They are difficult to reach and difficult to see for someone who wears glasses with bifocal lenses.
Frequent removal of the cryoprobe also puts wear on the system. Please let us know well in advance if you want to conduct solid-state NMR experiments on our 700 MHz instrument.