Nonlinear optical (NLO) crystals can be employed to expand the laser frequency and thus
are of technical importance in advanced laser science. Noncentrosymmetric rare earth
compounds keep attracting broad interest as a significant branch of NLO materials because
the highly distorted structural motifs centered by rare earth ions could remarkably benefit the
second harmonic generation. In this review, we proceed from structure–properties
relationship and reveal the role of rare earth element in the optical properties of NLO …