Ice and Beyond: Tetrahedral Building Blocks in Crystalsa

Tetrahedral building blocks are immensely important in inorganic materials. The structure of ice is ideal for presenting this concept, combined with an introduction to hydrogen bonding. Connecting tetrahedral building blocks is then extended to polymorphs of silica

The fungus Amanita muscaria: from neurotoxins to vanadium accumulation

The fungus Amanita muscaria contains neurotoxins which account for its long-time use as a hallucinogen. In contrast, A. muscaria is also a bioaccumulator of high levels of vanadium, the reason for which is still obscur

The sting's the thing

Bees defend themselves by stinging and injecting a venom into their victims; bee venom is a complex mixture of chemicals including the polypeptide melittin which is mainly responsible for triggering the pain of the stin

A new approach to the energetics of clusters and related systems

The work described in this thesis is concerned with cluster-species and related systems, many of which are electron deficient. The term 'electron deficient' is used to describe a polynuclear species in which there are too few valence electrons to allocate a localised 2-centre 2-eleotron bond to every pair of atoms which are within normal covalent bonding distance. The bonding in these systems may be rationalised instead in terms of the relationship between the total number of skeletal electrons provided by the skeletal cluster units, and the total number of skeletal atoms. The aim of this work is to suggest new ways in which bond enthalpy contributions can be allocated to individual 2-centre links in cluster systems. In order to obtain energy terms (E) which reflect changes in bond length, (d), relationships of the form E α d(^-k)(where k=constant; 2<k≤5) are proposed. Such empirical correlations are shown to be appropriate for simple main group systems and are applied in turn to boron hydrides, borane anions, transition metal carbonyls and to complexes containing multiple metal-metal bonds. Similar relationships are used to suggest possible bond orders in some systems. Finally, the extent to which skeletal electron counting methods may be used to rationalise the bonding in boranes, carboranes, transition metal complexes and small clusters, metal π-hydrocarbon complexes and small cyclic hydrocarbons is discussed

Nature's Chemical Weapons: Beetle Defenses

The defense chemicals secreted by beetles are very diverse. They are exemplified by those of members of the families Carabidae (ground beetles) and Coccinellidae (ladybirds)

Coordination Polymers and Metal-Organic Frameworks: Structures and Applications-A Themed Issue in Honor of Professor Christoph Janiak on the Occasion of His 60th Birthday

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Plant toxins: poison or therapeutic?

Many plants that are classed as poisonous also have therapeutic uses, and this is illustrated using members of the Drimia and Digitalis genera which are sources of cardiac glycosides

Memorial Issue Dedicated to Dr. Howard D. Flack: The Man behind the Flack Parameter

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Editorial: Materials for Energy Conversion

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