Publications

Infrared absorption spectra of metal complexes of alkylthioureas and some related ligands

The i.r. spectra of metal complexes of thioacetamide, thiourea, ethylenetrithiocarbonate, N-methylacetamide, N-methylthiourea, N,N′-dimethylthiourea and tetramethylthiourea have been examined in the 4000–4250 cm−1 region. The co-ordination is through sulphur in the complexes of thioacetamide, thiourea, ethylenetrithiocarbonate and tetramethylthiourea. N-methylthiourea and N-N′-dimethylthiourea show ambident behaviour wherein the co-ordination is through nitrogen or sulphur. It is difficult to assign structures of complexes on the basis of the frequency shifts particularly when the bands arise from mixed vibrations. Far i.r. spectra would, however, be useful in identifying metal-ligand vibrations.

ChemInform Abstract: Chemical Design of Solid Inorganic Materials

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Rare earth transition metal sulfides, LnMS3

Ternary rare earth transition metal sulfides LnMS3 with Ln = La, Nd, and Gd, and M = V and Cr; as well as Ln = La and M = Mn, Fe, Co, and Ni have been prepared and characterized. The vanadium and chromium sulfides crystallize in a monoclinic layer structure isotypic with LaCrS3, while the other LnMS3 sulfides crystallize in a hexagonal structure. Chemical shifts of the metal K-absorption edge and XPS binding energies of core levels indicate that the transition metal is trivalent in the V and Cr sulfides, while it is divalent in the Mn, Fe, Co, and Ni sulfides. Electrical and magnetic properties of the sulfides are discussed in terms of their structures and the electronic configurations of the transition metal ions.

CCDC 197437: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

ChemInform Abstract: The Liquid—Liquid Interface as a Medium to Generate Nanocrystalline Films of Inorganic Materials

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A Building‐Up Process in Open‐Framework Metal Carboxylates that Involves a Progressive Increase in Dimensionality

Zero- and one-dimensional metal carboxylates are shown to transform into higher-dimensional structures (see figure), thereby indicating the presence of a progressive building-up process.

Excerpts from Letters Read at the Conference

No abstract is provided for this article.

The infrared spectra of the salts of nitro compounds. Characteristic frequencies of the carbonitronate group, CNO2−

The infrared spectra of salts of nitro compounds have been studied and the N-O asymmetric and symmetric stretchings of the carbonitronate ion have been assigned to the regions 1316–1205 and 1175–1040 cm−1. The CN frequency of sodium alkanenitronates appears in the region 1605–1587 cm−1. The carbonyl and the nitrile stretching frequencies in α-nitroketones and α-nitronitriles are considerably reduced due to conjugation with the carbonitronate group.

Electronic transitions in hydrogen bonded dimers of carboxylic acids in the vapour phase: an electron energy loss spectroscopic study

An electron energy loss spectroscopic study of the formic acid dimer has shown bands centred around 7.2, 8.5, 9.8, and 11.1 eV, of which the first and the third bands are assigned to n–π* transitions and the other two to π–π* transitions; similar transitions are found in the acetic acid dimer.

Investigations of diamond–graphite hybrids and fullerenes with seven-membered rings

No abstract is provided for this article.

Metal chalcogenide–organic nanostructured composites from self-assembled organic amine templates

No abstract is provided for this article.

Dependence of the Reactivity of Ag and Ni Clusters Deposited on Solid Substrates on the Cluster Size

Bulk silver and nickel are less reactive than small clusters of these elements, as reactivity studies with O 2 as well as with H 2 S and CO prove. The dissociation of O 2 on small Ag clusters is favored, and the proportion of O 2 molecules cleaved does not depend upon temperature, as is the case for larger clusters and silver metal. The change in reactivity is greatest at the metal–insulator transition—a finding that has implications for heterogeneous catalysis.

MoS₂ and WS₂ Analogues of Graphene

Anorganische Schichten: Graphenartiges MoS2 und WS2 wurde durch drei verschiedene chemische Methoden hergestellt. Mikroskopische Untersuchungen offenbarten, dass die Strukturen aus einer oder wenigen Schichten aufgebaut sind (siehe TEM-Aufnahme von WS2-Schichten), und ein atomar aufgelöstes TEM-Bild zeigt, dass schichtförmiges MoS2 eine hexagonale Anordnung von Mo- und S-Atomen aufweist (siehe Einschub).

Spin state equilibria and localized versus collective d-electron behaviour in neodymium and gadolinium trioxocobaltate(III)

Magnetic susceptibility measurements and Mössbauer spectra show that NdCoO3 and GdCoO3 contain predominantly low-spin CoIII ions at low temperatures which transform partially to high-spin Co3+ until a certain temperature. Beyond this temperature, there is a transfer of eg electrons from Co3+ to CoIII giving rise to di- and tetra-valent Co species followed by short-range ordering. Co3+ ions completely disappear at about 1000 K where there is a gradual transition from localized electron behaviour to collective behaviour. The cobaltates are semi-metals beyond this transition. The spin state equilibria and the electronic transition described here find support from electron transport properties, Mössbauer parameters as well as differential thermal analysis and X-ray data.

Supercapacitors Based on Graphene, Borocarbonitrides and Molybdenum Sulphides

No abstract is provided for this article.

Oxyanion derivatives of cuprate superconductors: Superconducting 123 phosphates

Ferroelectric-like dielectric anomaly in RF-sputtered amorphous LiNbO3 films

Amorphous films of LiNbO3 prepared by RF sputtering exhibit ferroelectric-like dielectric anomaly just below the glass transition temperature. Electron microscopic studies show the presence of small crystalline clusters in the amorphous film. The dielectric anomaly however, seems to originate from the tissue material rather than from the clusters.

CCDC 181598: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.