Keywords: 2D; two-dimensional; 3D; three-dimensional; [ACnIm][N(CN)2]; 1-allyl-3-alkylimidazolium dicyanamide; β; hyperpolarizability; BBI; benzobis(imidazolium); [BBIm][Br]; 1,3-dibutylimidazolium bromide; [BH4]; tetrahydroborate; [BH2(CN)2]; dicyanoborate; [BH3C