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Axial circular dichroism (CD) of crystalline α-NiSO4 · 6H2O and α-ZnSeO4 · 6H2O is measured between 1900 and 5000 cm−1 at room temperature. Three CD bands with rotational strengths of 7 × 10−44, 3 × 10−44, and 1 × 10−42 erg · cm3 per molecule of water are observed at 5000, 4050, and 2300 cm−1, respectively, in α-NiSO4 · 6H2O. These CD bands are due to combination bands of H2O vibrations in the crystals. Substitution of H2O with D2O on α-NiSO4 · 6H2O shifts the 5000 cm−1 band to a frequency lower by the expected factor of 2. The 5000 and 4050 cm−1 CD bands are also observed in α-ZnSeO4 · 6H2O with the same intensities as in α-NiSO4 · 6H2O. Their positions are, however, shifted by 50 cm−1 toward higher energy. Due to strong absorption, the CD of fundamental vibrational modes of H2O in the crystals could not be measured. The CD is interpreted as a consequence of the linear k dependence of the effective charge of E mode optical phonons near k = 0.

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Measurements of the room temperature circular dichroism (CD) of the dimer of bis[3-(trifluoromethylhydroxymethylene)-i/-camphorato]cobalt reveal six bands between 1680 and 1200 cm-1. The observed CD is assigned to electronic transitions of Co2+ from the ground and first excited Kramers doublets to the higher Kramers levels of the 4Tib ground manifold, which is split by spin-orbit coupling and a ligand field of tetragonal symmetry. stretch), two strong peaks at 1745 and 1705 cm-1 (C=0 stretching modes), and a relatively strong band at 1650 cm-1 (C=C stretch of the enol form), in addition to the bands expected from the camphor skeleton and the CF3 group. These data agree with the ir study by Lintvedt and Fatta12 on methylhydroxymethylened-camphor and are those expected for a 3-diketone.Complexes. Complexes of tfhmc with the ions Co2+, Ni2+, Cu2+, and Fe2+ were prepared by dissolving the tfhmc in an ethanol: water mixture (7:3 v/v), adjusting the pH to 6-7, and adding to this mixture a solution of Co(N03)2, Ni(N03)2, CuCl2, or FeCl2 in the same ethanol:water solvent.13 Evaporation of the ethanol caused precipitation of the complex. The product was filtered, redissolved (11) K.

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