MERIX-Next generation medium energy resolution inelastic X-ray scattering instrument at the APS

► MERIX is a resonant inelastic X-ray scattering spectrometer, in hard X-ray regime. ► MERIX spanns atomic resonances near K-edges of 3d, and L-edges of 4f elements. ► MERIX offers its users a broad set of RIXS analyzers. ► The smallest intrinsic spectral resolution of the MERIX spectrometer is ≃45 meV. ► MERIX features ≃100 higher count-rates compared to previous RIXS spectrometers.