Atomically-thin layers of semiconducting transition metal dichalcogenides (TMDs), namely tungsten diselenide (WSe 2 ), have attracted considerable interest because of new properties that can be obtained when artificially fabricated into van der Waals superlattices. Interlayer coupling is responsible for various properties, including the indirect-to-direct band gap cross-over from bulk and few-layered to monolayer TMDs. It has also been demonstrated that twist angle can be used to tune the

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... ayer coupling strength in bilayer MoS 2 [1] and WS 2 [2] homostructures. In this work, the high spatial and spectral resolution of monochromated electron energy-loss spectroscopy (EELS) coupled with fourdimensional scanning transmission electron microscopy (4D-STEM) in an aberration-corrected STEM are used to investigate the excitonic response of twisted bilayer WSe 2 with a low moiré angle and the strain relaxation of those that are atomically reconstructed.