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Using a He-Ne CW laser source together with a digital photon counting system, we have obtained well resolved Raman spectra for adenosine mono-, di-, and triphosphate (AMP, ADP, ATP) in aqueous solution. Spectra of these compounds were studied as a function of pH from pH = 0.5 to 13.5 and between 550 and 1700 cm(-1). It was found possible to distinguish spectroscopically between the three phosphates over the pH range studied. A qualitative analysis of vibrational modes responsible for various spectral lines is given. Lines at about 960 and 1100 cm(-1) were found to be good indications of the degree of ionization of the terminal phosphate group.

Laser-excited Raman spectra of retinals (trans, 9-cis, 13-cis), retinols (trans, 13-cis), and trans-retinoic acid in octanol solution are reported. The terminal group is easily identified by the frequency of the line at 1580-1590 cm-l, while the isomer is uniquely characterized by the lines in the 1100-1400-~m-~ range. The observed spectra are mainly contributed by the conjugated segment and not by the saturated part of the molecule. A discussion of possible mode assignments is also presented.he observation of intense, resonance-enhanced,

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The infrared absorption spectra of boron oxide glasses of low and high water content have been obtained in the 400-to 4000-~m.-~ region using thin films or fine powders dispersed in a liquid. A structural interpretation of the glass spectra has been made with the aid of the spectra of the closely related materials boric acid, orthorhombic metaboric acid, and partly deuterated boron oxide glass of high water content. It has been shown that the glass spectra are consistent with a random-network structure in which each boron is triangularly coordinated by three oxygens and that the presence of water leads to weak hydrogen bonding between oxygen atoms. No evidence for a substantial amount of tetrahedral coordination of boron by oxygen has been found in glasses of either low or high water content.