Reliable, with one-point correction of energy scale
Comment:
A pure copper sample was first annealed under H2 (T = 1173 K, time = 90 min) and the sulfided in a gas mixture H2/H2S (T = 873 K, time = 6 h). For calibration, the Cu L3M45M45 transition at 334.95 eV was also used.