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Low-lying electronic states of TeF, whose emission results when hydrogen telluride and fluorine are intimately mixed, are reported. The emission spectrum in the region 5500–8600 Å would appear to result from the A2Πi–X2Πi transition. Based upon this observation, the previously reported system in the region 3900–5200 Å must be reassigned to the transition B2Σ+–X2Πi. Observed spectra are presented and vibrational and electronic constants for the A2Π, B2Σ+, and X2Π electronic states are tentatively assigned.

A careful synthesis of H2Te and D2Te and their isolation in solid argon are reported. Rare gas matrix isolated molecules of H2Te and D2Te were studied using Mössbauer spectroscopy. The gaseous species were identified using mass spectrometry. Mössbauer parameters were analyzed using extended Hückel calculations. A good agreement between the experimental and the calculated value of the quadrupole splitting requires a smaller quadrupole moment for the excited state of 125Te than that reported in the literature. A 10% increase in the QS for D2Te is explained as due to the enhancement of 〈1/r3〉 caused by a slight contraction of the D–Te bond.

The chemiluminescence which results when hydrogen telluride and fluorine are intimately mixed corresponds to an emission spectrum in the region 3900–5200 Å which appears to result from the previously unobserved TeF radical. The structure of the vibronic bands arising from transitions between 2Πi states has been assigned by analogy with the similar SF spectrum. The spectra corresponding to the A2Π3/2–X2Π3/2 and A2Π1/2–X2Π1/2 band systems appear to be well fit using the electronic and vibrational parameters T0(3/2–3/2) = 21 218 cm−1, T0(1/2–1/2) = 21 612 cm−1, we′ = 399 cm−1, wexe′ = 2.4 cm−1, we″ = 603 cm−1, and wexe″ = 4.0 cm−1. The difference in spin orbit constants for the ground and excited states is calculated to be 394 cm−1.

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