“…48 Although nonlinear optics has a long history in organic chemistry, the field of NLO in ligated noble metal nanoclusters is relatively new 49,50 , but fast-growing. [51][52][53] Due to molecular-like properties, it is expected that their NLO behaviour, in particular, their nonlinear refraction and absorption (including two-photon absorption, TPA) properties, could be understood in a way analogue to molecular materials. 52,54,55 In this feature article, we consider the current status of these investigations, with an emphasis on the joint work performed in our two groups.…”