Iron to sulfur bonding in cytochrome c studied by x-ray photoelectron spectroscopy

Nitrogen-Vacancy Magnetic Relaxometry of Nanoclustered Cytochrome C Proteins

“…45 Moreover, we corroborated the presence of Fe-sulfur bonds at binding energy of 167 eV through the examination of the high-resolution sulfur peak (Figure S2d). 46 The negatively charged NV center in the diamond lattice is a substitutional nitrogen adjacent to a vacancy site (Figure 2b) with a spin triplet in the ground state that features a zero-field splitting D = 2.87 GHz between states m s = 0 and m s = ±1 (Figure 2c). 19,21 A green laser illumination (532 nm) yields spin-conserving excitation to the excited triplet state, which in turn leads to far-red photoluminescence (650−800 nm).…”