Electron Spin Resonance and the Zeeman Effect: Experimental Determination of the Electron g-Factor

This laboratory report investigates electron spin resonance (ESR) and the Zeeman effect using a DPPH sample in an externally applied magnetic field. The interaction between electron spin magnetic moments and a homogeneous magnetic field was modeled theoretically, and resonance conditions were derived from quantum mechanical principles. Experimental measurements were performed using Helmholtz coils and radio-frequency excitation to determine resonance frequencies as a function of magnetic flux density. From the results, the electron g-factor was estimated and compared to the accepted reference value.The work illustrates key quantum mechanical concepts and was conducted as part of undergraduate experimental physics coursework at Aalto University.