Knowledge Bank

The molecular species were obtained by vaporization from a mixture of the respective metals and $M2S4$ solids except for Ti and Tl where the $M2S$ solids were used. The symmetric ($v1$) and antisymmetric ($\nu 3$) frequencies have been observed in various matrices for the Group IHA period Isotope shifts for $\nu 3$ due to $\mathrm{<mrow\; data-mjx-texclass="ORD">24</mrow>}S$ in natural abundance have also been measured in some cases. Isotope shift studies with $\mathrm{<mrow\; data-mjx-texclass="ORD">6</mrow>}$ Li and $\mathrm{<mrow\; data-mjx-texclass="ORD">7</mrow>}Li$ for the antisymmetric stretch ($\nu 3$) of $Li2S$ indicate a bond angle of 114$\pm$5$^\circ$.