O-D stretching vibration

Fig. 4.10 (A) The K minus bacteriorhodopsin difference infrared spectra measured at 77 K in the 2750-1930 cm 1 region. The spectra are compared between hydration with D20 (red lines) and D2lsO (blue lines). The gray curve in the 2700-2000 cnr1 region represents O-D stretching vibrations of D20. Green-labeled frequencies correspond to those identified as...

O—D stretching vibrations of water. This figure is modified from Kandori [98]. (A) Schematic drawing of the deuterated pentagonal cluster structure in the Schiff base. The numbers are the O—D stretching frequencies of water molecules in cm 1 assigned in the FTIR study. This figure is reproduced from Shibata and Kandori [95],... 

Ultrafast (femtosecond) pulsed two-color mid-infrared spectroscopy was used by Bakker et al. in a series of papers to study the effect of ions on the structural dynamics of their aqueous solutions as recently reviewed (Bakker 2008). The first intense pulse (pump pulse) excites the O-H (or O-D) stretch vibration to the first excited state and the second pulse (probe pulse), red-shifted with respect to the first, probes the decay of this state. This technique has been applied to aqueous (0.1-0.5 M HDO in D2O) solutions of LiX, NaX, and MgX2 (X = Cl, Br, I), KF, NaC104, and Mg(C104)2 over wide concentration ranges, 0.5-10 mol dm. ... 

Studies by IR and Raman spectrometry provide important information on the nature of water-water bonds. The O-D stretching vibration band in HDO solution containing 8.5 mol% D2O in H2O was measured at 303-673 K and 5-400 MPa and the result is depicted in Fig. 19 [64]. The O-D band was observed at 2520 cm under ambient condition. A sharp band appearing at 2719 cm in the solution of p = 0.0165 g cm and T = 673 K was ascribed to free HOD molecules. The band disappeared in SCW with p — 0.095 gcm . On the other hand, a new band was observed around 2650 cm in water with p = 0.036 gem and the intensity of the band increased and shifted toward the low frequency side with increasing density. In water with p = 0.9gem the band appeared at 2600 cm . The band was ascribed to the O-D frequency of hydrogen-bonded water in SCW. 

In the spectra of the carbon materials the band of stretching OH vibrations (3600-3100 cm" ) was due to surface hydroxy lie groups and chemisorbed water. The asymmetry of this band at lower wave numbers indicates the presence of strong hydrogen bonds. The same shape of O—H stretching vibrations of ammonia-treated carbon (D=N, Fig. 4) indicates that N—H (amine) structures are not formed during ammonia treatment. The presence of absorption bands characteristic of —CH, and —CH — structures (2960, 2920 and 2850 cm" ) in all the spectra suggests the existence of some aliphatic species on the carbons. 

Cyclic dimers of carboxylic acids represent important model systems forming two coupled intermolecular hydrogen bonds [Fig. 15.1 (d), inset of Fig. 15.4]. The linear vibrational spectra of carboxylic acid dimers have been studied in detail, both in the gas and the liquid phase, and a substantial theoretical effort has been undertaken to understand the line shape of their 0-H and/or O-D stretching bands. In contrast, there have been only a few experiments on the nonlinear vibrational... 

Previous assignments of bands characteristic of furanose and pyranose forms (Mathlouthi, Carbohydr. Res., 1980, 7, 225) were shown to be incorrect since these bands co-occur in the spectra of crystalline -D-fructopyranose. Prom the intensity of the carbonyl absorption in fructose solutions (the 0 -deuterated form in D-O) relative to that of diethyl ketone, it was concluded that 0.9 of fructose was present as the open-chain form. From a study of the i.r. spectra of peracetylated aryl glycosides, the value of bands in the 800-1000 cm region for differentiating a- and 6-anoraers has been reassessed. The relative intensities of C-O-C stretching vibrations in the 1000-1100 cm region and a band near 300 cm for -anomers only were suggested as criteria for... 

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