Reactions of 3,5-disubstituted-1,2,4-triazoles with CuX 2 (X = Cl, Br) under hydrothermal condition yield six copper(I) triazolates: [Cu 2 (3,5-n Bu 2 tz)Cl] n (1), [Cu 2 (3,5-i Bu 2 tz)Cl] n (2), {Cu 2 (3,5-(C 6 H 11 ) 2 tz)Cl} n (3), [Cu 2 (3,5-s Bu 2 tz)Br] n (4), {Cu 2 (3,5-(C 6 H 11 ) 2 tz)Br} n (5), {Cu 2 [3,5-(p-Tol) 2 tz]Br} n (6), where 3,5-n Bu 2 tz, 3,5-i Bu 2 tz, 3,5-s Bu 2 tz are 3,5-dibutyl-1,2,4-triazolate, 3,5-dii-butyl-1,2,4-triazolate, 3,5-dis-butyl-1,2,4-triazolate; 3,5-(C 6 H 11 ) 2 tz is 3,5-dicyclohexyl-1,2,4-triazolate; 3,5-(p-Tol) 2 tz is 3,5-di-p-tolyl-1,2,4-triazolate. X-ray analysis demonstrates that all of these complexes are isostructural and exhibit a 3D structure carrying cubic Cu 4 Cl 4 or Cu 4 Br 4 clusters. While 4 and 5 luminesce with maxima at 571 and 619 nm, others are silent under UV irradiation at room temperature.Keywords Copper(I) Á Triazole Á Structure Á Cu 4 Cl 4 cluster Á Cu 4 Br 4 cluster Electronic supplementary material The online version of this article (