Scanned-probe detection of electron spin resonance from a nitroxide spin probe SUPPORTING INFORMATION

The sample was prepared by dissolving 0.0063 g of TEMPAMINE (4-amino-2,2,6,6-tetramethylpiperidine-1oxyl; Aldrich, 163945) in 1 mL of d8-toluene, 0.33 mL of which was further diluted to 1 mL and from that, a 0.1 mL alliquot was added to a solution of 0.039 g deuterated polystyrene (Polymer Source, P4179B-dPS, Mn = 200×10 and Mw/Mn = 1.4) in 0.9 mL of d8-toluene. The resulting solution was spun at 2000 rpm for 30 s onto a 250 μm thick quartz chip (NOVA Electronics). Film thickness was determined by profilometry. A top coating of 20 nm of gold was electron-beam evaporated onto the chip at a rate of 0.2 nm/s. Samples for characterization by low temperature pulsed ESR were prepared identically, minus the gold, removed from the substrate and inserted into a 2 mm o.d. Suprasil tube.