A comparative study of carbonate bands from nanocrystalline carbonated hydroxyapatites using FT-IR spectroscopy in the transmission and photoacoustic modes

Solid-state MAS NMR, TEM, and TGA studies of structural hydroxyl groups and water in nanocrystalline apatites prepared by dry milling

“…1.0 wt % for HA24 and HA36, as estimated from the 1,415 cm −1 IR band (Kaflak et al 2011; Sønju Clasen and Ruyter 1997). For all studied samples, the content of A carbonates was immaterial (the A/B carbonate ratio below 0.05), as estimated from the 1,544 cm −1 IR band (Kaflak et al 2011; Sønju Clasen and Ruyter 1997). The concentrations of structural OH groups and water decreased and increased with the milling time, respectively (Table 1), and those findings will be of our particular concern in the following discussion.…”

“…40 %), the material was allowed to absorb ambient CO 2 and to undergo CO 3 2− substitutions for PO 4 3− groups (type-B carbonates) or for structural OH − groups (type-A carbonates). The contents of the A and B carbonates were estimated using the infrared method of Sønju Clasen and Ruyter (1997) and (Kaflak et al 2011). Spectroscopic FT-IR studies were carried out at 298 K on a Perkin Elmer Spectrum 1000 spectrometer.…”

“… a TEM (see Materials and methods and Online Resource 1) b From PXRD (Landi et al 2000) c In the 25–550 °C temperature range d From IR (Kaflak et al 2011; Sønju Clasen and Ruyter 1997) e From proton MAS NMR…”

Application of mid-infrared photoacoustic spectroscopy in monitoring carbonate content in soils

“…However, there is strong interference from water in the DRIFT spectrum at wavenumber positions where the carbonate bands are located. The stretching vibration of O H from water occurs in the region of 3200-3600 cm −1 and the O H bending vibration of H 2 O appears in the spectrum at 1550-1650 cm −1 [51]. Presence of the latter vibrational band significantly overlaps with the strongest and most pronounced carbonate vibration (1410 cm −1 ).…”

Effects of amino acids on conversion of calcium carbonate to hydroxyapatite

“…In addition, peaks observed at 3420 cm À1 and 1646 cm À1 are due to the tensile and exural vibrations of adsorbed water. 24 Peaks at 1429 cm À1 , 876 cm À1 , and 713 cm À1 are attributable to the antisymmetric expansion, out-of-plane bending, and inplane bending of CO 3 2À . 25 It indicates that part of CO 3 2À may enter HAp lattice and replace part of OH or PO 4 3À to form A-type or B-type HAp.…”