Beiträge zur Struktur und Chemie der Wollfaser

Ohne Zusammenfassung11. Mitteilung aus der Reihe Struktur und Reaktionsfäahigkeit der Wollfaser. 10. Mitteilung vgl. E. Elöd, H. Nowotny und H. Zahn, Klepzigs Textilzeitschrift45, 663 (1942).     

Zur Kenntnis der Chemie und der Struktur von Olefin-monocyano-dicarbonyl-ferrat-Anionen

About Chemistry and Structure of Olefin-monocyano-dicarbonyl-ferrate Anions By the reactions of olenFe(CO)₃ [olen = C₅H₈(isoprene), C₇H₁₀(cycloheptadiene-1,3), C₈H₁₄(2,5-dimethylhexadiene-1,3)] with sodium bis [trimethylsilyl]amide the new anions [olenFe(CO)₂CN]^? are formed. All so far known [olenFe(CO)₂CN]^? complexes [olen = C₅H₈(isoprene), C₇H₁₀[cycloheptadiene-1,3], C₄H₆(butadiene), C₅H₈(pentadiene-1,3), C₆H₈(cyclohexadine-1,3), C₆H₁₀(2,3-dimethylbutadiene), C₈H₈(cyclooctatetraene)] have fluctional structures in solution as shown by ¹³C NMR spectroscopic investigations. At low temperatures only the isomer exists, in which the CN^? ligand and one of the two CO molecules occuppy the basal positions of a square pyramide together with 2 C atoms of the diene part.     

Beiträge zur Chemie und Struktur von Vanadylhalogeniden

Investigations on the Chemistry and Structure of Vanadyl-halogenides Aqueous solutions of VOI₂ can be prepared from VOSO₄ and BaI₂. By concentrating VOI · 3 H₂O is formed; but adducts of VOI₂ with DMSO and DMF can be isolated. The structure of [VO(DMSO)₅]I₂ was determined by X-ray single crystal techniques: Monoclinic; space group P2₁/c; a = 10.696; b = 10.877; c = 24.74 Å; ß = 109.87°; Z = 4. – Other new compounds are VO(OCH₃)Br · 3 pyr and VOBr₂ · 2 H₂O · 2 eth, which can be decomposed to VOBr₂. The structures of VOCl₂ and VOBr₂ were determined from crystal powders (space group I mmm). IR and reflection spectra (4–50 kK) and magnetic moments of all compounds were measured.     

Zur Chemie und Strukturchemie der Phosphide und Polyphosphide. 20. Darstellung,Struktur und Eigenschaften der Alkalimetallmonophosphide NaP und KP

Chemistry and Structural Chemistry of Phosphides and Polyphosphides. 20. Preparation, Structure, and Properties of the Alkali Metal Monophosphides NaP and KP The monophosphides NaP and KP were prepared by reaction of the elements in sealed glass ampoules at 725 K and 765 K, respectively. NaP yields as black reflecting needles, whereas KP is formed as microcrystalline substance with colour of coke. The compounds react very rapidly with aqueous reagents forming solid polymeric yellow phosphanes (PH)_x and partially gaseous products. NaP and KP crystallize in the novel orthorhombic NaP type (P 2₁2₁2₁; a = 603,8 pm; b = 564.3 pm; c = 1 014.2 pm and a = 650.0 pm; b = 601.6 pm; c = 1 128.8 pm; Z = 8, respectively) characterized by onedimensional infinite ¹∞(P^?) helices of covalent twofold bonded P-atoms with mean bond length P? P = 223.9 pm. The compounds can be described as Zintl-phases with M⁺ and P^? with respect to the structure. The range of existence of the NaP type and the LiAs type structure can be separated by the radii ratios. The volume increment for P^? is V(P^?) = 18.0 cm³mol^?1. For the bond energy E(P? P) in the monophosphides a value of 248 kJ · mol^?1 is calculated. The structures are discussed in detail together with related compounds.     

Zur Chemie und Strukturchemie von Phosphiden und Polyphosphiden. 42. Trilithiumheptaphosphid Li3P7: Darstellung,Struktur und Eigenschaften

Chemistry and Structural Chemistry of Phosphides and Polyphosphides. 42. Trilithiumheptaphosphide Li₃P₇: Preparation, Structure, and Properties Trilithium heptaphosphide, Li₃P₇, has been prepared by reaction of the elements at 870 K in Nb and Ta ampoules, respectively. The bright yellow (solventfree) substance crystallizes in a new structure type (P2₁2₁2₁; a = 974.2(1) pm; b = 1053,5(1) pm; c = 759,6(1) pm; Z = 4). The structure is closely related to the plastically crystalline Rb₃P₇ type of structure (Li₃Bi variant). The heptaphosphanortricyclene anions P₇^3? are surrounded by 12 Li cations and connected one to each other in a complex manner. The anion exhibits a differentation of distances and angles typical for ionic nortricyclenes X₇^3? (P? P distances: d?(basis) = 224.9 pm; d?(basis-bridge) = 214.7 pm; d?(bridge-bridgehead) = 217.6 pm). The distances Li to P are in the range of 250 ≤ d(Li? (2b)P^?) ≤ 270 pm. The P? P and Li? P bond distances are equivalent to meaningful Pauling bond orders PBO. On heating in closed ampoules, Li₃P₇ shows an endothermic effect at 900 K, corresponding to a first order phase transition into a HT phase of unknown nature up to now. On thermal decomposition no congruent dissociative sublimation occurs in contrast to the other heptaphosphides M₃P₇, but LiP and Li₃P are formed, the latter evaporates congruently dissociative, Solutions of Li₃P₇ in en show valence fluctuation of the P₇^3? anions already at room temperature (δ ³¹P-NMR = ? 122.1). Further reactions of Li₃P₇ are reported as well as the structural differences between Li₃P₇ and the solvates Li₃P_7solv3 are discussed.     

Chemie und Verbrechen

Man has been under the spell of crime since the times of Kain and Abel, so why not put it to work in motivating chemistry students? Forensic work in the chemistry lab leads to a whole lot of interesting chemical principles and the students get acquainted with several advanced experimental methods.