Centrosymmetric to noncentrosymmetric structure transition of the RbREP 2 Se 6 (RE = La–Nd, Sm, Ho–Yb) series: crystal growth, magnetic and optical properties

Crystals of RbREP 2 Se 6 (RE = La–Nd, Sm, Ho–Yb) exhibit a monoclinic-to-orthorhombic transition with decreasing rare earth size. RbNdP 2 Se 6 and RbSmP 2 Se 6 showed SHG efficiencies of ∼0.67, and ∼3.65 × AgGaS 2 .