D 460 cm1 are redshifted in comparison to kaolinite spectra,Agronomy 2021, 11,12 ofwhile the band of 455 cm1, the principal band in kaolinite, is either insignificant or significantly decrease in intensity in HS. The bands at 775 and 750 cm1 don’t belong to quartz lattice frequencies, and they don’t shift, that is clear from comparing with neighboring quartz bands. Likewise, the band at 715 cm1 will not be attributed to any lattice bands of quartz or silicate minerals, and its position will not alter with temperature to ensure that it can be the manifestation of OM, inphase rock CH2 vibrations of C4 alkanes [69], or polyaromatic entities [67]. A rather broad band at 70000 cm1 with primary components at 640 cm1 and 610 cm1 is attributed to water librations [73]. Its intensities reduce with temperature (Figure 3), which contrasts with all the behavior of other bands in this region. Both bands disappear at Bifeprunox Description temperatures of 750 . This behavior is in league with water bands at 1640 cm1 and 3690 cm1 as well as the hydrogenbond ensemble (see Sections 3.4.3 and three.4.5 below) attributed to loosely bound water. Water absorption decrease with temperature reveals a weak band at 67065 cm1, which will not shift together with the temperature and may perhaps be attributed to CO2. A band at 425 cm1 is usually attributed to C vibrations, but that is rather Solvent Yellow 93 Protocol spurious resulting from its low intensity and only trustworthy look in the SigmaAldrich sample. three.four.two. QuartzOvertoneBand Area (127000 cm1) All bands within this area encounter a redshift with equivalent parameters (Figure 4) ex cept for the carbonate band at 875 cm1 (Figure 5). Following the literature [32], they are overtone lattice bands in quartz shifting resulting from changing lattice parameters [90]. Broad bands at about 1030 cm1 (Figure six) and 1120070 cm1 (Figure 7) can be regarded as the total SiO2 elements as they may be characteristic of each amorphous and crystalline species [32,68,80,90,91]. Nonetheless, the band behavior at 1030 cm1 is related to that of 1010 cm1.Figure 4. Redshifts in the smoothed bands at 1032 cm and 797 cm relative to 25 temperature for HS samples.1 Having said that, the band at 1120070 cm1 is absent in kaolinite, so it may possibly be partially attributed to HSOM (inplane C bending of nonaromatic and cellulose species [92]). Nevertheless, if we stick to the notion of temperatureindependent nonquartz vibrations, no such components are identified within this broad band. It may be deconvoluted into two components at 1110 cm1 and 1070 cm1 that experience equivalent and synchronous redshifts, so they will have to be attributed to quartz overtone components. This band is roughly exactly the same as the dual structure of temperature experiments for quartz samples. The carbonate band at 875 cm1 and its companion at 840 cm1 is visible at low temperatures (Figure 4), significantly less affected by water bands, and doesn’t decrease at the finish with the temperature cycle. 3.4.three. HSOM Region (1780270 cm1) All bands except for 1380 cm1 (Figure 8) and 1580 cm1 (Figure 9) are temperature independent, that is evidence that they are not overtone counterparts of matrix vibra tions of quartz and belong to isolated group vibrations. The pair of 1580 cm1 andAgronomy 2021, 11,13 ofcm1 (antisymmetric and symmetric carboxylate stretches, respectively) is dominated by combination vibrations [93,94] and behaves as expected (like hydrogenbond ensem bles), Figure 10. The antisymmetric band exhibits a blueshift, when the counterpart sym metric band shows a redshift. The antisymm.