NMR spectroscopy was performed using a Bruker Avance 300 (300.13 MHz, 1H; 75.5 MHz, 13C), with a BBFO probe. NMR spectra were processed using the Bruker TOPSPIN 3.0 software.
NMR spectroscopy was performed using either a Bruker Avance 300 (300.13 MHz, 1H; 75.5 MHz, 13C), an Avance III 400 (400.13 MHz, 1H; 100.6 MHz, 13C) with a Prodigy cryoprobe CPPBBO, an Bruker Avance III 500 (500.13 MHz, 1H; 125.7 MHz, 13C) with a TBI probe or an Bruker Avance III 600 (600.13 MHz, 1H; 150.9 MHz 13C). NMR spectra were processed using the Bruker TOPSPIN 3.0 software.
NMR general characterisation analyses were conducted using a Bruker Avance III 300 spectrometer (1H, 300.17 MHz). Further characterisation was conducted using a Bruker Avance III 600 spectrometer (1H, 600.13 MHz) with a BBFO probe and an Avance III 500 spectrometer (1H, 500.13 MHz) with a TBI probe. The 600 MHz and 500 MHz spectrometer parameters were: 8390 Hz sweep width, 1.95 s acquisition time, 2 s recycle delay; 6009 Hz sweep width, 5.45 s acquisition time, 5 s recycle delay; respectively. The excitation sculpting pulse program was used for water suppression.(1) Samples were analysed in the solvents d6-DMSO and D2O. All chemical shifts are stated in ppm (δ) relative to tetramethylsilane (δ = 0 ppm), referenced to the chemical shifts of residual solvent resonances (1H and 13C). 31P spectra were calibrated to H3PO4 (85 %) (δ = 0 ppm).
(1) T.-L. Hwang & A.J. Shaka, J. Magn. Reson., Series A 112 275-279 (1995)
Pulse program references All pulse program references can be found at the top of the pulse program within Topspin within the relevant experiment.
Probes on different instruments Gyro - Bruker Avance III 300, 5 mm BBFO probe Rabi - Bruker Avance III 400, 5 mm BBFO+ probe Pines - Bruker Avance III 300, 2.5, 4 and 7 mm MAS probes Gauss - Bruker Avance III 400, 5 mm CPPBBO probe Weber - Bruker Avance III 400, 5 mm BBFO probe Hertz - Bruker Avance III 500, 5 mm TBI probe Tesla - Bruker Avance III 600 , 5 mm BBFO or TBI probe Ernst - Bruker Avance III HD 600, 5 mm TCI probe Felix - Bruker Avance III 700, 5mm TXI or BBI probe, 1.3, 2.5, 4 mm MAS probes, 4 mm HRMAS probe, 4mm Low Gamma HRMAS probe.
Notes The exact frequency for any nucleus used in an experiment can be obtained by looking for the "sfo1" parameter within the experiment. All of the relevant parameters listed are stored within each experiment. Be sure to include the mechanisms used to quantify the chemical shift.