Previous articles have dealt with the special problems arising when attempting to reduce reducible representations in continuous point groups. Current work, involving the programing of "projection operators" in connection with numerical computations, also shows the continuous groups to present special problems. These problems are…

Explores the question "Why are so many stationary states allowed by traditional quantum mechanics not realized in nature?" through discussion of classical observables and superselection rules. Three examples are given that can be used in introductory courses (including the fermion/boson property and the mass of a "nonrelativistic" particle). (JN)

Discusses the valence-bond method, applying it to some coordination compounds of metals, especially those involving metal-metal bonds. Suggests that transition metals can form as many as nine covalent bonds, permitting valence-theory to be extended to transition metal compounds in a more effective way than has been possible before. (JN)

Discusses structures and characteristics of sulfur compounds which cause the odor of garlic and the crying which may result from an onion. These compounds are dependent on conditions of extraction and account for medical properties long ascribed to garlic and onions. (DH)

Highlights five major analytical areas (electrophoresis, immunoassay, chromatographic separations, protein and DNA sequencing, and molecular structures determination) and discusses how analytical chemistry could further improve these techniques and thereby have a major impact on biotechnology. (JN)

This short article consists of some thoughts derived from a longer paper (Palmer, 1992), together with some more recent ideas. I became interested in buckminsterfullerene (Buckyballs) as a result of an E-Mail discussion of the topic in 1991. The chemistry of buckyballs is now evolving very rapidly and is gradually creeping into school…

Describes a visual transparency method to develop the concept of resonance with respect to molecular resonance hybrid structures and partial charge on the atoms of an ion. Discusses the distinction between tautomerism and resonance, and emphasizes clarification of the Lewis structure concept. (JM)