Xenon reacts with fluorine to form XeF(2) which can be isolated before it reacts with fluorine to form XeF(4). The linear configuration of XeF(2) with the 2.00-A bond length and the vibrational force constants support the assignment of 10 electrons to the valence shell of xenon. Similar arguments support the assignment of 12 and 14 valence electrons respectively to xenon in XeF(4) and XeF(6).

The OH radiation intensity in the 3064 Å band, the temperature, and the OH concentration were measured as a function of the height above the face of a premixed H2/O2 flat flame burner. The burner was operated fuel lean at subatmospheric ambient conditions. Examination of possible reaction mechanisms that could produce chemiluminescent OH radiation from these hydrogen-lean flames led to results consistent with those obtained in hydrogen-rich flames. The termolecular rate coefficient for the reaction H+OH+OH→H2O+OH* was found to be (2.3±0.9) × 10−32 cm6 molecules−2 · sec−1. The value represents an upper bound for the rate coefficients of the reactions which might contribute to the excitation of OH.

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The quenching behavior of neutral metastable species during collisions with a neutral partner is investigated. Usually, radiationless energy transfer can be described by invoking the radiation field as an intermediary between interacting molecules. However, for metastables, the dominant radiation transition moments are suppressed, most often by spin selection rules between the excited and ground energy states. The fast reaction rates for the quenching of the metastables suggest a different intermediary for such cases. Motivated by this phenomena, a two-electron exchange process is proposed as the quenching mechanism. During a collision, it is envisioned that the excited outer shell electron of the metastable effectively undergoes a change of molecular center and is replaced by an electron from the collision partner. The theoretical framework for this process is developed using the formalism of molecular quantum electrodynamics. The electron exchange term is obtained explicitly, using the minimal-coupling method.