Chemical-bond effect of pion-capture ratios in some alkali-metal compounds

Abstract

Pion-capture ratios have been measured for fluorides, hydroxides, and tetrahydroborates of alkali metals. The ratios for hydroxides agree with those for fluorides, when OH is taken as a group. However, though it is expected that tetrahydroborates have similar ionic bonding as fluorides and hydroxides, capture ratios of the alkali metal to the ${\mathrm{BH}}_{4}$ group are enhanced when compared with those of the alkali metal to the F or OH groups. Obtained capture ratios are analyzed with a modified mesomolecular model and the effect of chemical bonding on the capture ratios is discussed.