Londa L. Borer

High-resolution infrared spectra, physical properties, and micromorphology of serpentines

Abstract Separate serpentine minerals may be identified by near infrared (NIR) spectra using remote sensing or portable field devices, and identified in the laboratory by NIR and mid-infrared spectra, but X-ray diffraction (XRD) procedures are necessary for rapid identification of serpentine mineral mixtures. Compacted serpentine aggregate material is very stable with a density of about 2400 kg/m 3 having an internal friction angle of about 32° with weak cementation. Non-fibrous clinochrysotile, the most common serpentine mineral in California deposits, consists of densely packed tubules from 600 to 700 A diameter, which are too short to be considered asbestiform. The Picrolite fibers are brittle and too large to be asbestiform.

Physical properties of selected illites, beidellites and mixed-layer illite–beidellites from southwestern Idaho, and their infrared spectra

Abstract The silver–gold ore deposits of the De Lamar mine, the mines in Florida Mountain and the mines in War Eagle Mountain occur in conjunction with large seams of clay minerals, which consist mainly of mixed-layer illite–beidellite. When saturated with groundwater, these clay seams have caused slope failures during mining and processing of ore. The illite–beidellite clays have effective internal friction values, O e , as low as 4° and cementation C values of about 1.0 kg f/cm 2 . The Fe-beidellite used for the clay core of the mill pond dam has an average O e value of 8.3° and C value of 0.79 kg f/cm 2 , with an average permeability ( K -value) of 5.6×10 −7 cm/s. The fundamental OH spectra of beidellite, illite and muscovite are similar with beidellite having bands near 3635, 3654 and 3653 cm −1 . Montmorillonite has one Al–OH libration band near 915 cm −1 , whereas beidellite has a second band near 942 cm −1 . In like manner, illites and muscovites have bands from 928 to 933 cm −1 , as well as the Al–OH libration bands from 912 to 917 cm −1 . The OH libration bands vary both in position and intensity with particle orientation and heating. Combination bands for Fe-bearing muscovite show moderate bands at 4451 cm −1 for ferrous muscovite and at 4471 cm −1 for ferric muscovite. These bands also are present for illites. The dominant Al–OH combination band wave numbers of muscovites form a linear relationship with the Al 2 O 3 muscovite contents, but not so precisely for illites. Chemical analysis of illites indicates that the compositions are a continuum into muscovites. Illites from the Miller–Walters mine contain a rather large amount of certain trace elements, whereas the adjacent beidellites do not.

Octahedral Nickel(II) dithiocarboxylates

Abstract Two nickel(II) complexes, NiL 2 Cl 2 and NiL 2 – (NO 3 ) 2 ·0.3EtOH, with the ligand 1,3-dimethyl- imidazoliumdithiocarboxyalato (L) have been synthesized and characterized by infrared and electronic spectroscopy and magnetic susceptibilities. The complexes exhibit the normal paramagnetism characteristic of octahedral nickel(II). The magnetic moments decrease with falling temperature, indicative of antiferromagnetic coupling, which is greater for the chloride than for the nitrate adduct. Columnar structures with chloro and nitrato bridging are proposed.

Metal complexes of 1,3-dimethylimidazolium-2-dithiocarboxylate

Abstract Complexes containing the soft acid metals Pt, Pd, Ag, and Au, with the ligand 1,3-dimethylimidazolium-2-dithiocarboxylate (L) have been synthesized and characterized by analytical data and infrared and electronic spectroscopy. The data suggest that the ligand acts as a bidentate ligand with Pt and Pd, a monodentate ligand with Ag and a bridging ligand between two Au atoms.

Synthesis and characterization of o-benzoquinonediiminebis(o-phenylenediamine)ruthenium(II) hexafluorophosphate

Abstract The title compound, o-benzoquinonediiminebis(o-phenylenediamine)ruthenium(II) hexafluorophosphate, has been synthesized and characterized by crystal structure, IR, UV–Vis and NMR spectroscopy.

Epoxidation of cyclic olefins using dimeric molybdenum(VI) catalysts

Abstract Catalytic properties of dimeric molybdenum(VI) triketonates were compared to those of MoO 2 (acac) 2 in the epoxidation reaction of cyclooctene and 1,5-cyclooctadiene with tertiary butyl hydroperoxide. Studies of the reaction at a molar ratio of olefin:TBHP:catalyst= 1:1:0.001 for the monoolefin and 1:2:0.001 for the diolefin at 40 and 80 °C in dichloroethane were carried out. The dimeric Mo(VI) complexes preferentially catalyzed the production of a monoepoxide.