Calculations of the structural and thermodynamic characteristics of copper carbonates by quantum-chemical methods

Revisiting the Raman Spectra of Carbonate Minerals

“…For a better understanding of the related parameters, the discussion will follow considering the observations made about the Raman shift, the bandwidth, and the relative intensity. for the COO bending mode, there are three bands, which can be seen at 719 cm −1 (𝐴 symmetry), 750 cm −1 (𝐵 symmetry), and 818 cm −1 (𝐴 symmetry) [43].…”

“…The azurite (monoclinic mineral) Raman spectrum can be divided into three types of modes: the CO 3 2− , OH − and Cu-O modes [16,43]. Taking into account only the carbonate ions in the azurite structure, there are 24 vibrational modes:…”

“…For the asymmetrical stretching of the C-O bond, there are three bands, which are observed at 1416 cm −1 (A g symmetry), 1428 cm −1 (B g symmetry), and 1456 cm −1 (A g symmetry). For the symmetrical stretching of the C-O bond, there is one band at 1094 cm −1 (A g symmetry), and for the COO bending mode, there are four bands at 740 cm −1 (B g symmetry), 763 cm −1 (A g symmetry), 814 cm −1 (B g symmetry) and 837 cm −1 (A g symmetry) [16,43]. Furthermore, for malachite (a monoclinic mineral), there are 15 vibrational modes:…”

“…For the asymmetrical stretching of the C-O bond, there are two bands at 1460 cm −1 (B g symmetry) and 1490 cm −1 (A g symmetry). For the symmetrical stretching of the C-O bond, there are two bands at 1066 cm −1 (A g symmetry) and 1100 cm −1 (B g symmetry), and for the COO bending mode, there are three bands, which can be seen at 719 cm −1 (A g symmetry), 750 cm −1 (B g symmetry), and 818 cm −1 (A g symmetry) [43].…”

“…For malachite, Frost and collaborators described the free carbonate ions on the basis of a D 3h point group [16]; however, Bissengaliyeva has shown in a theorical approach that the carbonate ion oxygen atoms of malachite are situated in triangular vertices where the valence angles at carbon are noticeably different from 120 • , displaying a symmetry which is somewhat different from the equilateral triangle symmetry D 3h [43]. In this last study, Bissengaliyeva has given three different force constants values for O-C-O bonds in three different environments: 0.80, 0.82 and 1.00 mdyn/Å [43]. The symmetrical stretching mode splits, becoming three bands at 1100, 1066, and 1008 cm −1 .…”