Growth, structural, vibrational, DFT and thermal studies of bis(β-alanine) nickel(II) dihydrate crystals

Bis(β-alanine) nickel(II) dihydrate single crystals were grown from an aqueous solution through the slow evaporation method, in 2:1 M ratio of amino acid:metal. The structural, vibrational and thermal properties were studied by X-ray powder diffraction, Raman and Fourier-transform infrared spectroscopy and thermal analyses. Additionally, all the Raman and infrared bands were assigned by means of density functional theory calculations to aid a better interpretation of the intramolecular vibrational modes. The results showed that the complex belonged to a triclinic system with P1-space group and had the following lattice parameters: a = 8.362 (7), b = 6.723 (7), c = 4.909 (4) Å, α = 103.72 (6)°, β = 94.66 (6)° and γ = 102.16 (4)°. The thermal, X-ray diffraction and Raman analyses indicated a phase transformation from the triclinic crystalline phase to anhydrous phase due to a loss of water of crystallization. [Display omitted] •The obtained Ni(β-alan)2·2H2O crystals were blue rhomb-shaped platelets.•The TG curve indicates that the thermal decomposition proceeds by two steps.•The XRD results show a gradual amorphization of the material.•Raman spectra suggest that hydrogen bonds are highly affected by temperature.