Darstellung und Eigenschaften einiger Bis- und Tris(diphenylphosphino)di-, tri- und tetrasilane

Dimethyldichlorosilane, 1,2-dichlorotetramethyldisilane, 1,3-dichlorohexamethyltrisilane and methyltris(chlorodimethylsilyl)silane react with diphenylpotassiumphosphide. The resulting bis- and tris(diphenylphosphino)silanes are characterized by IR and²⁹Si as well as³¹P-NMR-spectroscopy.

     

Quantification of total petrol hydrocarbons (TPH) in soil by IR-spectrometry and gas chromatography – conclusions from three proficiency testing rounds

Due to the utilisation of 1,1,2-trichlorotrifluoroethane (CFE) as extraction solvent the IR-spectrometric determination of total petrol hydrocarbon (TPH) in soil according to ISO/TR 11046 has been replaced by gas chromatography/flame ionisation detection (GC/FID) after extraction with a halogen-free solvent according to ISO/DIS 16703:2001. The results obtained with both methods by field laboratories in three proficiency testing (PT) rounds are compared. The consensus means obtained with GC/FID are typically 10%–20% (ranging between 0% and 25%) higher than those found with IR-spectroscopy. On the contrary, coefficients of variation (CV) are roughly double in case of GC/FID and are briefly discussed against the background of the Horwitz equation. Received: 19 November 2001 Accepted: 17 March 2002     

Electronic structure of the radicals NF and NCI. I. Potential energy curves for NF

Large-scale MRD CI calculations are employed to determine the potential energy curves for the 1π⁴2π², 1π³2π³ and 5σ1π⁴2π³, 1π⁴2π6σ states of NF as well as that of the lowest state of the positive NF⁺ ion. Vertical transition energies to states up to 10 eV are given. In contrast to OZ the ;(5a → 2π) and ³(2π -> 6a) states are found below those arising from the 1π³2π³ configuration. Numerous avoided crossings between states occur, primarily at larger internuclear separations, which cause, for example, a barrier to WE' dissociation and a distinct minimum in the 1¹Σ⁺ curve.     

2-Spiro-indan-1,3-dione

The reaction of 1,3-indandione, formaldehyde and primary amines does not gives doubleMannich bases as described in literature, but the title compounds.

Herrn Professor Dr.F. Bohlmann zum 60. Geburtstag gewidmet.