Achieving Phase‐Matching in Nonlinear Optical Materials CsM2In2S6 (M = Cd/In, Hg/In) by the Incorporation of Unprecedented Trigonal Planar MS3 Motifs

The trigonal planar unit possesses significant hyperpolarizability and polarizability anisotropy, which makes it useful for optimizing nonlinear optical (NLO) materials, however, chalcogenide with this unit has seldom been reported. In this work, a novel approach is introduced by integrating the unprecedented trigonal planar MS