Crystal structure, computational study and nonlinear optical properties of the novel copper(I) π,σ-complexes based on 3,4-diphenyl-5-allylsulfanyl-4H-1,2,4-triazole

•Novel Cu(I) π,σ-complexes with allyl-substituted 1,2,4-triazole were obtained by ac-technique.•Crystal structures construction details discussed.•Optimized geometry and Raman spectra assignments were found using DFT calculations.•Laser stimulated non-linear optics studied. This work is devoted to the synthesis, structure characterization, and nonlinear optical properties investigation of the novel copper(I) η2-π-complexes [CuICuII(Dphatr)Br3] (1), [Cu2(Dphatr)2(CF3COO)2]∙H2O (2), [Cu2(Dphatr)2(C6H5SO3)2] (3), and [Cu2(Dphatr)2(CH3C6H4SO3)2]∙2CH3OH (4) based on 3,4-diphenyl-5-allylsulfanyl-4H-1,2,4-triazole (Dphatr). The distinguishing feature of structure 1 is the presence of two crystallographically independent copper ions (Cu(I) and Cu(II)), each of which have a markedly different coordination environment and form an infinite inorganic chain. The structures of 2–4 are constructed from the isolated centrosymmetric dimers, formed by two π,σ-coordinated copper(I) ions, by two pairs of N atoms of triazole cycles, and by O atom of an anionic part. Energy frameworks computational analysis for Dphatr structure has been performed. Measurements of the generation of the second harmonic of the light were performed in the reflected mode using a pulsed Nd:YAG fs laser. [Display omitted]