Isotope effects in liquid water by infrared spectroscopy. III. H2O and D2O spectra from 6000tocm−1

Abstract

The infrared spectra (IR) of pure liquid light (H(2)O) and heavy (D(2)O) water were obtained with attenuated total reflection (ATR) and transmission measurements in the mid-IR and far-IR. With these and with other values obtained from the literature, the real (n) and imaginary parts (k) of the refractive index were meticulously derived in the complete IR region from 6000 to 0 cm(-1). The reliability of the results resides in the critical comparison of our experimental data with that obtained from other laboratories and between calculated and experimental spectra, obtained by ATR and transmission techniques. The new optical properties (n and k) can now be used as standards for liquid H(2)O and D(2)O. To these we have added the water (H and D) absorption coefficients (K) that are derived from the k values. These can be used as references for spectra obtained by transmission with an absorbance intensity scale because they are almost the same.

Changes in the hydrogen-bonding strength of internal water molecules and cysteine residues in the conductive state of channelrhodopsin-1

“…This is in agreement with the ∼30% smaller absorption coefficient of the O-D stretch than of the O-H stretch of water. 13,65 The narrower bands in D 2 O are also coherent with the longer lifetime of the O-D stretch compared to the O-H stretch. 3 We conclude that CaChR1 contains a water molecule in the dark state with a weakly Hbonded O-H group.…”

Structural Models of Water and Ice Regarding the Energy of Hydrogen Bonding

“…These librations are due to the restrictions imposed by hydrogen bonding (minor L 1 band at 395,5 cm -1 ; major L 2 band at 686,3 cm -1 ; for liquid water at 0 0 C, the absorbance of L 1 increasing with increasing temperature, while L 2 absorbance decreases but broadens with reduced wave number with increasing temperature [44]. The IR spectra of liquid water usually contain three absorbance bands, which can be identified on absorption band of the stretching vibration of OH -group; absorption band of the first overtone of the bending vibration of the molecule HDO and absorption band of stretching vibration of OD -group [45]. Hydroxyl group OH -is able to absorb much infrared radiation in the infrared region of the IR-spectrum.…”

Studying of Isotopic Effects of Deuterium in Biological Objects

“…These librations are due to the restrictions imposed by hydrogen bonding (minor L1 band at 395,5 cm -1 ; major L2 band at 686,3 cm -1 ; for liquid water at 0 0 C, the absorbance of L1 increasing with increasing temperature, while L2 absorbance decreases but broadens with reduced wave number with increasing temperature [42]. The IR spectra of liquid water usually contain three absorbance bands, which can be identified on absorption band of the stretching vibration of OHgroup; absorption band of the first overtone of the bending vibration of the molecule H 2 НO and absorption band of stretching vibration of OD -group [43]. Hydroxyl group OH -is able to absorb much infrared radiation in the infrared region of the IR-spectrum.…”