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Three compounds that display the skew-pentagonal-pyramid (SPP) [C.sub.s]-[C.sub.60][X.sub.6] or [C.sub.s]-[C.sub.60][X.sub.4]O addition patterns are described. All three compounds have demonstrated that the SPP addition pattern is at least kinetically stable and the high temperature synthesis of the two epoxides have indicated that perfluoroalkyl substituents can enhance the thermal stability of fullerene derivatives with other substituents.

The isolation of 1,9-and 1,7-C60F(CF3) from a high-temperature C60/K2Pt F6 reaction mixture is described. It was found that the dominant coupling mechanism is through-space coupling rather than through-bond coupling.

The mechanism of formation of fluorofullerene (FF) negative ions derived from the compounds C60F18, C60F36, and C60F48 is examined by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (ToF) mass spectrometry (MS). A combined experimental approach provides compelling evidence of nondissociative, thermodynamically controlled electron transfer from matrix-derived negative ions to the FF analyte as the main secondary-ionization process.

The improved synthetic and isolation procedures are developed that resulted in the preparation of pure C(sub 60)F(sub 20) in sufficient amounts for comprehensive vibrational spectroscopic studies. The results provide a vibrational assignment for the original conjecture of the C(sub 60)F(sub 20) structure with the equatorial belt of 20 fluorine atoms on C(sub 60) cage.

Development of a new quantitative method for determining low concentrations of aqueous polyatomic anions using attenuated total reflectance (ATR) FTIR spectroscopy is described. Evaporated thin-film coatings of anion-selective tetraalkylated ferrocenium salts were applied to the surface of ATR crystals, which enabled anion detection limits to be lowered up to 23 000-fold below those achieved using the commercially available spectrometer with identical uncoated ATR crystals. Linear calibration curves based on d(absorbance)/dt, which is related to the rate of anion exchange in the thin film, were established in the 0.04-30 [micro] M range. Limits of detection (10-min analyses) for perchlorate, chlorate, trifluoromethanesulfonate, perfluoro-n-butanesulfonate, perfluoro-n-octanesulfonate, tetrafiuoroborate, hexafluorophosphate, and pinacolylmethylphosphonate in aqueous solution were 0.03, 0.2, 0.05, 0.07, 0.06, 0.06, 0.6, and 0.7 [micro] M, respectively, using the thin-film coatings. This simple detection/quantification method afforded good reproducibility with relatively fast detection times.

Research has been conducted on metal cations, including silver. The secondary bonding of these cations to halogen donor atoms on the weakly coordinating anions has been characterized via the use of nuclear quadrupole resonance spectroscopy and X-ray crystallography and the details are reported.

An approach developed for teaching descriptive inorganic chemistry courses involves presenting a limited set of facts about several elements or several compounds. The facts are not memorized, but used as jumping-off points for inquiry into whys and wherefores of the chemistry of the elements. Stoichiometries of known, stable binary compounds is a fundamental aspect of descriptive chemistry, but it is not interesting to memorize a list of chemical formulas when d-metals compound stochiometry is studied.

Results demonstrate that HA(sub)2 anions, formed by oxoanions A(sup)-hydrogen-bonding to their conjugate acids HA, are weaker than their A(sup)- counterparts in ion pairing and coordination. Data further show that HA(sub)2 in association with carboxylates or sulfonates coordinate more weakly than their parent anions as revealed by infrared spectroscopic studies.

An interesting way to introduce periodic trendshas been developed for undergraduate inorganic chemistry courses. The student investigates the significantly different M(super.2+/0) E degree values for adjacent period-4 elements zinc and copper with guidance of an instructor. The project is handled as though it were research and periodic trends and anomalies are discovered as knowledge is needed. The student sees that deep understanding of reactivity comes when complexity is worked thorough a layer at a time and that there is always more to learn.