The infrared spectra of liquid, solid, and gaseous tetradeuterated hydrazine have been measured from 250 to 4000 cm−1. Fine structure was resolved for three of the perpendicular fundamental bands of the assumed symmetric top. The Raman spectra of liquid hydrazine and tetradeuterated hydrazine have been recorded and depolarization values measured. A complete vibrational analysis based on band type, position, and depolarization values is given which satisfies the product rule for both the a and b vibrational symmetry species. The intensity of the 3189-cm−1 band of hydrazine has been studied as a function of temperature. ΔH° for H-bond formation in hydrazine is found to be − 1450 cal/mole. The relative intensity of the 3189-cm−1 band to that of the 3260-cm−1 band has been studied as a function of concentration in dimethylsulfoxide and indicates that part of the intensity of the 3189-cm−1 band arises from a vibrational mode of the hydrazine monomer.

Vibrational Raman spectroscopy was used in investigate the conformational behavior of dipalmitoylphosphatidylcholine (DPPC) bilayers perturbed by cholesterol and water, two membrane components whose lipid interactions involve different regions of the bilayer matrix. Upon the addition of cholesterol, an intrinsic membrane constituent, to an anhydrous bilayer in concentrations varying from 7 to 30 mol %, modifications in lateral chain interactions were observed by monitoring spectral changes in the methylene C-H stretching and the CH2 deformation regions. The perturbation in the 1460-cm-1 region was not spectroscopically observed until after the addition of 7 mol % of the sterol. Although chain-chain interactions are altered, no additional trans/gauche isomerization is developed along the hydrocarbon chains. Water, a peripheral bilayer component, was added to the multilayer assembly in the hydration range of 0.3 to 4 molecules of water per lipid molecule. Vibrational spectra characteristic of motions in the head-group, interfacial, and acyl chain regions of the lipid bilayer were observed. These data indicate that hydration confers a mobility to the head-group, glycerol, and carbonyl moieties. Shifts in the CN symmetric and PO2-antisymmetric stretching modes, occurring on the addition of approximately four molecules of water, indicate a conformational rearrangement within the polar head group. After approximately four molecules of water are added to the DPPC system, the spectral features of the gel system [70% (w/w) water] indicate that not further head-group changes nor increases in either acyl chain trans/gauche or lattice disorder arise on further hydration.

The infrared spectra of solid and matrix-isolated methylamine, methylamine-d2, methyl-d3-amine, and methyl-d3-amine-d2 have been recorded from 4000 to 250 cm−1. The Raman spectra of the four isotopic species have also been recorded and depolarization values measured. The elusive NH2 twisting vibration has been located in the solid-phase infrared spectra of CH3NH2 and CD3NH2, and the assignment is in agreement with both the product rule and earlier assignments for this normal mode in hydrazine. A temperature-dependent hydrogen-bonding study has been carried out and ΔH° for H-bond formation in methylamine-d2 was found to be −660 cal/mole.

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Raman spectra of concentrated aqueous solutions of ferric chloride were recorded in the spectral range 50 to 500 cm−1. In near-saturated solutions, spectra show a four-line pattern typical of the tetrahedral FeCl4– complex: 390 cm−1 (w); 335 cm−1 (vs, p); 135 cm−1 (w); 110 cm−1 (s). At lower concentrations a new species dominates the spectrum, showing characteristic Raman lines at 318 cm−1 (s, p) and 165 cm−1 (vw). Conventional investigations of spectral changes with concentration of Fe(III) and chloride, coupled with group theoretical arguments, indicate that the stoichiometry of the complex must be FeCl3 or lower. Of the several symmetries that a FeCl3 complex might assume (C2v, C3v, D2h (dimer), and D3h), the D3h trigonal bipyramid structure FeCl3·2H2O with three equatorial chloride ligands and two axial waters is most compatible with the spectral evidence.