The infrared spectrum of polyethylene has been obtained between about 3000 cm-1 and 70 em-I, polarization measurements on oriented specimens having been obtained to about 350 em-l. Assignments of the fundamentals are made with the help of a group theory analysis. The assignment of the controversial CH. wagging mode is discussed in detail and especially in terms of new evidence from the spectra of n-paraffins, both as single crystals and as polycrystalline aggregates. It is shown that this mode is to be assigned to a weak band at 1369 cm-l. A satisfactory determination of the bands which arise from CHa groups is also made possible by a study of the paraffin spectra. The splitting of bands in the spectrum is conclusively shown to arise from interactions between molecules in the crystalline phase. The nature of this interaction is discussed in terms of recent theories.

The infrared spectrum of polyvinyl alcohol has been investigated between 3600 and 70 cm.−1. Polarization measurements on stretched specimens were made down to about 330 cm.−1. The spectrum of a deuterated specimen (about 90% of the OH having been replaced by OD) has also been obtained. These data confirm and extend the results of previous workers. The spectrum is discussed in detail in relation to three structures for polyvinyl alcohol proposed on the basis of x‐ray diffraction studies. The data definitely rule out the structure proposed by Mooney, and are most consistent with the structure proposed by Bunn. A complete assignment of the bands in the spectrum is proposed. From this analysis it appears that the existence of interaction forces between molecules can be convincingly demonstrated. The proposed assignments suggest a new interpretation of the 1326–1446 cm.−1 doublet, viz., that these bands arise from mixed CH and OH in‐plane bending vibrations. This is shown to be in agreement with the results of studies on simple alcohols. An alternative assignment for the 1144 cm.−1 band is also considered.

The effects of hydrogen bonding on the infrared spectra of aliphatic alcohols have been studied in the range 4000 to 350 cm-I. Twenty-six alcohols were investigated of which 10 were primary, 7 were branched primary, 6 were secondary, and 3 were tertiary. Attention was concentrated on the region of the spectrum between 1500 cm-I and 350 em-I where the deformation vibrations of the OR group occur. Spectra were obtained of the alcohols (a) in dilute solution in nonpolar solvents, (b) in the liquid state, and (c) in the vapor state, the degree of association being followed by observation of the well-known effect of hydrogen bonding in the OR stretching vibration near 3.01", Methanol, ethanol, and hexanol-1 were also investigated after deuteration of the OR group. All the alcohols exhibited a broad diffuse association band with a maximum near 650 em-I. This has been assigned to the out-of-plane deformation vibration of the R atom in the COR group. All the alcohols also exhibited a broad association band which usually had 2 maxima near 1410 cm-I and 1330 em-I. This band (which appears to have been missed by previous workers) is assigned to the in-plane deformation vibration of the R atom in the COR group. The corresponding monomeric band varies between 1200 cm-I and 1330 cm-I in undeuterated alcohols and between 870 cm-I and 930 cm-I in deuterated alcohols. There is in addition a very narrow association band which lies near 1100 cm-I in primary and secondary alcohols and near 1165 cm-I in tertiary alcohols. This is assigned to the effect of hydrogen bonding on the skeletal vibrations, which involve stretching of the CO bond. It appears that the effects of hydrogen bonding on the deformation motions of the OR group are quite complex and that steric effects, rotational isomerism, and interaction with C-R deformation frequencies may all be involved to some extent.

Gem minerals at Lava Plains, northeast Queensland, offer further insights into mantle-crustal gemformation under young basalt fields. Combined mineralogy, U-Pb age determination, oxygen isotope and petrological data on megacrysts and meta-aluminosilicate xenoliths establish a geochemical evolution in sapphire, zircon formation between 5 to 2 Ma. Sapphire megacrysts with magmatic signatures (Fe/Mg ∼100–1000, Ga/Mg 3–18) grew with ∼3 Ma micro-zircons of both mantle (δ18O 4.5–5.6%) and crustal (δ18O 9.5–10.1‰) affinities. Zircon megacrysts (3±1 Ma) show mantle and crustal characteristics, but most grew at crustal temperatures (600–800°C). Xenolith studies suggest hydrous silicate melts and fluids initiated from amphibolized mantle infiltrated into kyanite+sapphire granulitic crust (800°C, 0.7 GPa). This metasomatized the sapphire (Fe/Mg ∼50–120, Ga/Mg ∼3–11), left relict metastable sillimanite-corundum-quartz and produced minerals enriched in high field strength, large ion lithophile and rare earth elements. The gem suite suggests a syenitic parentage before its basaltic transport. Geographical trace-element typing of the sapphire megacrysts against other eastern Australian sapphires suggests a phonolitic involvement.

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