Nesbitt's group combines high-resolution laser spectroscopy, chemical physics and single-molecule fluorescence/FRET microscopy to probe molecular structure, dynamics, and biophysics at the single-molecule limit, spanning gas-phase reaction dynamics to nanoscale biomolecular conformational sensing. For context, this complements the established paradigm of NV-diamond ensemble magnetometry (Hahn-echo/DEER, nanoscale NMR, T1 relaxometry) operating near pT/√Hz sensitivity.