Unstable intermediates. Part LXXXVIII. Alkali-metal interaction with trapped hydrogen atoms in barium sulphate

Abstract

Barium sulphate doped with various alkali-metal salts gave, on exposure to ⁶⁰Co γ-rays at 77 K, two types of trapped hydrogen atoms, one of which had e.s.r. spectra characterised by hyperfine coupling to the alkali-metal cations. For example, the species NaH⁺ had g_av= 2·0013, a_‖(¹H)= 513·2 G, a_⊥(¹H)= 510·7 G, a_‖(²³Na)= 21·4 G and a_⊥(²³Na)= 15·1 G.

These results, together with data for other host crystals, are discussed in terms of the structure of the adducts and their stability.