A review of the AI2BIICIVDVI4 family as infrared nonlinear optical materials: the effect of each site on the structure and optical properties

Inorganic infrared (IR) second-order nonlinear optical (NLO) crystals have become increasingly important for fulfilling the demands of modern laser technology through frequency conversionviaoptical parametric oscillation (OPO) and optical parameter amplification (OPA) technology. The AI2B(II)C(IV)DVI4 family contains a large number of compounds (to our best knowledge, 102 formula) and shows abundant structural diversity; it could be regarded as a potential source of IR second-order NLO materials with tunable structures and properties. This article summarizes the authors' contributions to the AI2B(II)C(IV)DVI4 family, together with other reported related results where the NLO properties have been provided (a total of 38 compounds). In the title family: (1) the A(I)site can be occupied by the univalent coinage metals Cu and Ag or the alkali metals Li and Na; (2) the B(II)site involves divalent metals, including the alkaline earth metals (AEM) Sr and Ba or the d(10)metals Zn, Cd, and Hg; (3) the C(IV)site is prevalently IVA group semi-conducting Si and Ge, or Sn; and (4) the D(VI)site is S or Se. The structures and optical properties of these compounds are summarized and the influence of substitution at each site on the structures and properties is systematically analyzed.