C. Clifford Addison

The N4O62+ group: X-ray crystal structure of Fe(NO3)3,1·5N2O4

The crystal structure of the adduct Fe(NO3)3,–1·5N2O4 indicates that it should be represented as 3NO+,NO3–,2[Fe(NO3)4–]; vibrational spectroscopy provides evidence for interaction between the NO3– and 3NO+ ions, and the properties are correlated in terms of a weakly bonded N4O62+ group which may also be present in solutions of N2O4, or the adduct, in pure nitric acid.

Chemistry in fuming nitric acids—I. NMR spectroscopic study of PF5, HPO2F2 and P4O10 in the solvent system 44 wt.% N2O4 in 100% HNO3

Abstract 31 P and 19 F NMR spectroscopy has been used to elucidate the nature of the interaction of PF 5 , HPO 2 F 2 and P 4 O 10 with the solvent system 44 wt.% N 2 O 4 in 100% HNO 3 (“High Density Acid”, HDA). PF 5 generates the species PF 6 − , HPO 2 F 2 and HF (with some H 2 PO 3 F present as a minor product). HPO 2 F 2 gives rise to H 2 PO 3 F and HF (with smaller amounts of PF 6 also present). The 31 P NMR spectrum of P 4 O 10 in HDA exhibits four resonances assigned to P(OH) 4 + , H 4 P 2 O 7 , (HPO 3 ) 4 and a mixture of cyclic and branched phosphoric acids, respectively.

Hexa-μ-nitrato-μ4-oxo-tetraberyllium

Crystal structure determination of the title compound, [Be4O(NO3)6], confirms the expectation of a molecular structure similar to that of basic beryllium acetate [Tulinsky & Worthington (1959). Acta Cryst. 12, 626–634].

The reaction of ionic nitrites with liquid dinitrogen tetraoxide

Abstract The reaction of nitrites of Na + , Bu 4 n N + and Ni 2+ with liquid dinitrogen tetraoxide and the factors affecting the rate and extent of the reaction have been studied. Oxidation occurs to the corresponding nitrate in a manner consistent only with the heterolytic dissociation of N 2 O 4 into NO + and NO 3 − . The synthesis of anhydrous Ni(NO 2 ) 2 is described in detail.

Solutions of salts in liquid sodium electrical resistivity of solutions of sodium hydride and of sodium monoxide, and the solubility of sodium hydride in sodium

Abstract The electrical resistivity of solutions of sodium hydride (between 340 and 430 °C) and of sodium monoxide (at 400 °C) in liquid sodium up to saturation concentrations has been determined. The resistivity increases linearly with increasing concentration of each salt but hydride ions scatter conduction electrons more effectively; unit resistivity increases are 4.5 × 10 −8 and 1.8 × 10 −8 Ω m (mol.%) −1 for H − and O 2− , respectively, which may reflect the difference in size of the solvated anions. The solubility of sodium hydride was determined from the change in resistivity which occurred on saturation. Values are combined with those derived from pressurecomposition isotherms to give the solubility equation: Iog 10 ( mol .% H ) = 4.82 − 3600/ T 613 ⩽ T ⩽ 673 K

Mössbauer study of the thermal decomposition of dinitrogen tetroxide solvates of iron(III) nitrate

The thermal decomposition of the 1·5 N2O4 solvate of iron(III) nitrate, [N4O6]2+2[Fe(NO3)4]–, has been investigated. Four isolable intermediates, [NO]+[Fe(NO3)4]–, [NO2]+[Fe(NO3)4]–, [Fe2O(NO3)4], and [FeO(NO3)], have been characterised, the ultimate product being Fe2O3. [Fe2O(NO3)4] and [FeO(NO3)] both exhibit room temperature Mossbauer effects characteristic of polymeric lattices. The Mossbauer spectra of the complexes M+[Fe(NO3)4]–[M = Me4N, EtnNH4 –n(n= 1–4), N4O6+, or NO2+] and M+[FeCl4]–[M = EtnNH4 –n(n= 1–4)] all consist of a single resonance with isomeric shifts in the ranges 0·54–0·61 mm s–1 and 0·30–0·31 mm s–1, respectively. The two nitrosonium salts, [NO]+[FeX4]–(X = Cl, NO3), however, exhibit small quadrupole splittings (Δ= 0·36 mm s–1, X = Cl; Δ= 0·45 mm s–1, X = NO3), which are attributed to the interaction of the highly polarising nitrosonium cation with one of the ligands X.

Reaction between barium and nitrogen in liquid sodium: solubility studies

Nitrogen in increasing amounts has been added to separate solutions of barium in sodium of constant composition (ca. 4.40 mol % Ba) at 300 °C. After rendering each mixture homogeneous using an electromagnetic pump, filtration, and nitrogen analysis, all the N2 added has been found in solution up to a solution composition approximating to Ba4N (i.e. 1.1 mol % N) beyond which the quantity of dissolved N2 decreases progressively due to precipitation of the nitride Ba2N. The solubilization is interpreted in terms of strong preferential solvation of the nitride ion by barium cations.

Derivatives of pentacarbonylnitratorhenium(I) with some nitrogen, phosphorus, and arsenic donor ligands

Reactions of pentacarbonylnitratorhenium(I) with pyridine (py), 2,2′-bipyridyl (bipy), 2,2′2″-terpyridyl (terpy), triphenylphosphine, and triphenylarsine yield the fac-disubstituted derivatives, Re(CO)3L2NO3, in which the covalent metal–nitrate bond is retained. Tricarbonylnitratobis(triphenylphosphine)rhenium(I) has been shown to exhibit fac–mer isomerisation.

Heat of mixing of dinitrogen tetroxide with organic liquids

Heat is absorbed when dinitrogen tetroxide is mixed with non-polar non-donor liquids, and is evolved on mixing dinitrogen tetroxide with polar or donor liquids. Heats of mixing at different concentrations of 16 binary mixtures containing dinitrogen tetroxide are reported.

Novel co-ordination numbers in scandium(III) and yttrium(III) nitrato-comlplexes. X-ray crystal structures of Sc(NO3)3.2N2O4 and Y(NO3)3.2N2O4

X-Ray crystallographic studies of the anions [Sc(NO3)5]2– and [Y(NO3)5]2–, which have been prepared using liquid N2O4, have revealed novel co-ordination numbers of nine for scandium(III) and ten for yttrium(III), with geometries best described in terms of a pseudotrigonal bipyramid.