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Melaminium N -acetylglycinate dihydrate, an organic material has been synthesized and characterized by X-ray diffraction, FT-IR, and FT-Raman spectroscopies for the protiated and deuteriated crystals. The title complex crystallizes in the triclinic system, and the space group is P-1 with a = 5.642(1) Å, b = 7.773(2) Å, c = 15.775(3) Å, α = 77.28(1)°, β = 84.00(1)°, γ = 73.43(1)° and Z = 2. The molecular geometry, vibrational frequencies and intensity of the vibrational bands have been interpreted with the aid of structure optimization based on density functional method (B3LYP) with the 6–311++G(d,p) basis set. The obtained vibrational wavenumbers and optimized geometric parameters were seen to be in good agreement with the experimental data. The intermolecular hydrogen bonding interactions of the title compound have been investigated using the natural bonding orbital analysis. It reveals that the O-H···O, N-H···N and N-H···O intermolecular interactions significantly influence crystal packing of this molecule. The non-linear optical properties are also addressed theoretically. The predicted NLO properties of the title compound are much greater than ones of urea. In addition, DFT calculations of the title compound, molecular electrostatic potential, thermodynamic properties, frontier orbitals and chemical reactivity descriptors were also performed at 6–311++G(d,p) level of theory. [ABSTRACT FROM AUTHOR]

Highlights: [•] Crystal structure was solved with single crystal X-ray measurements. [•] Solid state vibrational spectra of anilinium trichloroacetate were interpreted. [•] DFT calculations were performed. [•] Second harmonic generation efficiency was measured. [•] Role of hydrogen bonds in NLO phenomenon is analysed. [•] Frontier molecular orbitals and NBO analysis were done. [Copyright &y& Elsevier]

The crystals of the new melaminium arsenate (MAS) [C 3 H 7 N 6 + ⋅H 2 AsO 4 − ] were obtained by the slow evaporation of an aqueous solution at room temperature. Single crystal X-ray diffraction analysis reveals that the crystal belongs to triclinic system with centro symmetric space group P−1. The crystals are built up from single protonated melaminium residues and single dissociated arsenate H 2 AsO 4 − anions. The protonated melaminium ring is almost planar. A combination of ionic and donor–acceptor hydrogen-bond interactions linking together the melaminium and arsenate residues forms a three-dimensional network. Vibrational spectroscopic analysis is reported on the basis of FT-IR and FT-Raman spectra recorded at room temperature. Hydrogen bonded network present in the crystal gives notable vibrational effect. DSC has also been performed for the crystal shows no phase transition in the studied temperature range (113–293 K). [ABSTRACT FROM AUTHOR]