Electronic structure of the quasi-two-dimensional spin-gap system SrCu2(BO3)2: Experiment and theory

The electronic structure of the quasi-two-dimensional spin-gap system SrCu2(BO3)2 is investigated using a combined experimental and theoretical approach based on electron energy loss spectroscopy (EELS) and first-principles band structure calculations. We show that the local-density approximation (LDA)+U method, guided by the experimental O-K edge recorded in EELS, provides a simultaneous accurate description of both low-energy-scale (magnetic) …